| @ignore |
| Copyright (C) 2005, 2006, 2007 |
| Free Software Foundation, Inc. |
| This is part of the GNU Fortran manual. |
| For copying conditions, see the file gfortran.texi. |
| |
| Permission is granted to copy, distribute and/or modify this document |
| under the terms of the GNU Free Documentation License, Version 1.2 or |
| any later version published by the Free Software Foundation; with the |
| Invariant Sections being ``GNU General Public License'' and ``Funding |
| Free Software'', the Front-Cover texts being (a) (see below), and with |
| the Back-Cover Texts being (b) (see below). A copy of the license is |
| included in the gfdl(7) man page. |
| |
| |
| Some basic guidelines for editing this document: |
| |
| (1) The intrinsic procedures are to be listed in alphabetical order. |
| (2) The generic name is to be used. |
| (3) The specific names are included in the function index and in a |
| table at the end of the node (See ABS entry). |
| (4) Try to maintain the same style for each entry. |
| |
| |
| @end ignore |
| |
| @tex |
| \gdef\acos{\mathop{\rm acos}\nolimits} |
| \gdef\asin{\mathop{\rm asin}\nolimits} |
| \gdef\atan{\mathop{\rm atan}\nolimits} |
| \gdef\acosh{\mathop{\rm acosh}\nolimits} |
| \gdef\asinh{\mathop{\rm asinh}\nolimits} |
| \gdef\atanh{\mathop{\rm atanh}\nolimits} |
| @end tex |
| |
| |
| @node Intrinsic Procedures |
| @chapter Intrinsic Procedures |
| @cindex intrinsic procedures |
| |
| @menu |
| * Introduction: Introduction to Intrinsics |
| * @code{ABORT}: ABORT, Abort the program |
| * @code{ABS}: ABS, Absolute value |
| * @code{ACCESS}: ACCESS, Checks file access modes |
| * @code{ACHAR}: ACHAR, Character in @acronym{ASCII} collating sequence |
| * @code{ACOS}: ACOS, Arccosine function |
| * @code{ACOSH}: ACOSH, Hyperbolic arccosine function |
| * @code{ADJUSTL}: ADJUSTL, Left adjust a string |
| * @code{ADJUSTR}: ADJUSTR, Right adjust a string |
| * @code{AIMAG}: AIMAG, Imaginary part of complex number |
| * @code{AINT}: AINT, Truncate to a whole number |
| * @code{ALARM}: ALARM, Set an alarm clock |
| * @code{ALL}: ALL, Determine if all values are true |
| * @code{ALLOCATED}: ALLOCATED, Status of allocatable entity |
| * @code{AND}: AND, Bitwise logical AND |
| * @code{ANINT}: ANINT, Nearest whole number |
| * @code{ANY}: ANY, Determine if any values are true |
| * @code{ASIN}: ASIN, Arcsine function |
| * @code{ASINH}: ASINH, Hyperbolic arcsine function |
| * @code{ASSOCIATED}: ASSOCIATED, Status of a pointer or pointer/target pair |
| * @code{ATAN}: ATAN, Arctangent function |
| * @code{ATAN2}: ATAN2, Arctangent function |
| * @code{ATANH}: ATANH, Hyperbolic arctangent function |
| * @code{BESJ0}: BESJ0, Bessel function of the first kind of order 0 |
| * @code{BESJ1}: BESJ1, Bessel function of the first kind of order 1 |
| * @code{BESJN}: BESJN, Bessel function of the first kind |
| * @code{BESY0}: BESY0, Bessel function of the second kind of order 0 |
| * @code{BESY1}: BESY1, Bessel function of the second kind of order 1 |
| * @code{BESYN}: BESYN, Bessel function of the second kind |
| * @code{BIT_SIZE}: BIT_SIZE, Bit size inquiry function |
| * @code{BTEST}: BTEST, Bit test function |
| * @code{CEILING}: CEILING, Integer ceiling function |
| * @code{CHAR}: CHAR, Integer-to-character conversion function |
| * @code{CHDIR}: CHDIR, Change working directory |
| * @code{CHMOD}: CHMOD, Change access permissions of files |
| * @code{CMPLX}: CMPLX, Complex conversion function |
| * @code{COMMAND_ARGUMENT_COUNT}: COMMAND_ARGUMENT_COUNT, Get number of command line arguments |
| * @code{CONJG}: CONJG, Complex conjugate function |
| * @code{COS}: COS, Cosine function |
| * @code{COSH}: COSH, Hyperbolic cosine function |
| * @code{COUNT}: COUNT, Count occurrences of TRUE in an array |
| * @code{CPU_TIME}: CPU_TIME, CPU time subroutine |
| * @code{CSHIFT}: CSHIFT, Circular shift elements of an array |
| * @code{CTIME}: CTIME, Subroutine (or function) to convert a time into a string |
| * @code{DATE_AND_TIME}: DATE_AND_TIME, Date and time subroutine |
| * @code{DBLE}: DBLE, Double precision conversion function |
| * @code{DCMPLX}: DCMPLX, Double complex conversion function |
| * @code{DFLOAT}: DFLOAT, Double precision conversion function |
| * @code{DIGITS}: DIGITS, Significant digits function |
| * @code{DIM}: DIM, Positive difference |
| * @code{DOT_PRODUCT}: DOT_PRODUCT, Dot product function |
| * @code{DPROD}: DPROD, Double product function |
| * @code{DREAL}: DREAL, Double real part function |
| * @code{DTIME}: DTIME, Execution time subroutine (or function) |
| * @code{EOSHIFT}: EOSHIFT, End-off shift elements of an array |
| * @code{EPSILON}: EPSILON, Epsilon function |
| * @code{ERF}: ERF, Error function |
| * @code{ERFC}: ERFC, Complementary error function |
| * @code{ETIME}: ETIME, Execution time subroutine (or function) |
| * @code{EXIT}: EXIT, Exit the program with status. |
| * @code{EXP}: EXP, Exponential function |
| * @code{EXPONENT}: EXPONENT, Exponent function |
| * @code{FDATE}: FDATE, Subroutine (or function) to get the current time as a string |
| * @code{FGET}: FGET, Read a single character in stream mode from stdin |
| * @code{FGETC}: FGETC, Read a single character in stream mode |
| * @code{FLOAT}: FLOAT, Convert integer to default real |
| * @code{FLOOR}: FLOOR, Integer floor function |
| * @code{FLUSH}: FLUSH, Flush I/O unit(s) |
| * @code{FNUM}: FNUM, File number function |
| * @code{FPUT}: FPUT, Write a single character in stream mode to stdout |
| * @code{FPUTC}: FPUTC, Write a single character in stream mode |
| * @code{FRACTION}: FRACTION, Fractional part of the model representation |
| * @code{FREE}: FREE, Memory de-allocation subroutine |
| * @code{FSEEK}: FSEEK, Low level file positioning subroutine |
| * @code{FSTAT}: FSTAT, Get file status |
| * @code{FTELL}: FTELL, Current stream position |
| * @code{GERROR}: GERROR, Get last system error message |
| * @code{GETARG}: GETARG, Get command line arguments |
| * @code{GET_COMMAND}: GET_COMMAND, Get the entire command line |
| * @code{GET_COMMAND_ARGUMENT}: GET_COMMAND_ARGUMENT, Get command line arguments |
| * @code{GETCWD}: GETCWD, Get current working directory |
| * @code{GETENV}: GETENV, Get an environmental variable |
| * @code{GET_ENVIRONMENT_VARIABLE}: GET_ENVIRONMENT_VARIABLE, Get an environmental variable |
| * @code{GETGID}: GETGID, Group ID function |
| * @code{GETLOG}: GETLOG, Get login name |
| * @code{GETPID}: GETPID, Process ID function |
| * @code{GETUID}: GETUID, User ID function |
| * @code{GMTIME}: GMTIME, Convert time to GMT info |
| * @code{HOSTNM}: HOSTNM, Get system host name |
| * @code{HUGE}: HUGE, Largest number of a kind |
| * @code{IACHAR}: IACHAR, Code in @acronym{ASCII} collating sequence |
| * @code{IAND}: IAND, Bitwise logical and |
| * @code{IARGC}: IARGC, Get the number of command line arguments |
| * @code{IBCLR}: IBCLR, Clear bit |
| * @code{IBITS}: IBITS, Bit extraction |
| * @code{IBSET}: IBSET, Set bit |
| * @code{ICHAR}: ICHAR, Character-to-integer conversion function |
| * @code{IDATE}: IDATE, Current local time (day/month/year) |
| * @code{IEOR}: IEOR, Bitwise logical exclusive or |
| * @code{IERRNO}: IERRNO, Function to get the last system error number |
| * @code{INDEX}: INDEX, Position of a substring within a string |
| * @code{INT}: INT, Convert to integer type |
| * @code{INT2}: INT2, Convert to 16-bit integer type |
| * @code{INT8}: INT8, Convert to 64-bit integer type |
| * @code{IOR}: IOR, Bitwise logical or |
| * @code{IRAND}: IRAND, Integer pseudo-random number |
| * @code{ISATTY}: ISATTY, Whether a unit is a terminal device |
| * @code{ISHFT}: ISHFT, Shift bits |
| * @code{ISHFTC}: ISHFTC, Shift bits circularly |
| * @code{ITIME}: ITIME, Current local time (hour/minutes/seconds) |
| * @code{KILL}: KILL, Send a signal to a process |
| * @code{KIND}: KIND, Kind of an entity |
| * @code{LBOUND}: LBOUND, Lower dimension bounds of an array |
| * @code{LEN}: LEN, Length of a character entity |
| * @code{LEN_TRIM}: LEN_TRIM, Length of a character entity without trailing blank characters |
| * @code{LGE}: LGE, Lexical greater than or equal |
| * @code{LGT}: LGT, Lexical greater than |
| * @code{LINK}: LINK, Create a hard link |
| * @code{LLE}: LLE, Lexical less than or equal |
| * @code{LLT}: LLT, Lexical less than |
| * @code{LNBLNK}: LNBLNK, Index of the last non-blank character in a string |
| * @code{LOC}: LOC, Returns the address of a variable |
| * @code{LOG}: LOG, Logarithm function |
| * @code{LOG10}: LOG10, Base 10 logarithm function |
| * @code{LOGICAL}: LOGICAL, Convert to logical type |
| * @code{LONG}: LONG, Convert to integer type |
| * @code{LSHIFT}: LSHIFT, Left shift bits |
| * @code{LSTAT}: LSTAT, Get file status |
| * @code{LTIME}: LTIME, Convert time to local time info |
| * @code{MALLOC}: MALLOC, Dynamic memory allocation function |
| * @code{MATMUL}: MATMUL, matrix multiplication |
| * @code{MAX}: MAX, Maximum value of an argument list |
| * @code{MAXEXPONENT}: MAXEXPONENT, Maximum exponent of a real kind |
| * @code{MAXLOC}: MAXLOC, Location of the maximum value within an array |
| * @code{MAXVAL}: MAXVAL, Maximum value of an array |
| * @code{MCLOCK}: MCLOCK, Time function |
| * @code{MCLOCK8}: MCLOCK8, Time function (64-bit) |
| * @code{MERGE}: MERGE, Merge arrays |
| * @code{MIN}: MIN, Minimum value of an argument list |
| * @code{MINEXPONENT}: MINEXPONENT, Minimum exponent of a real kind |
| * @code{MINLOC}: MINLOC, Location of the minimum value within an array |
| * @code{MINVAL}: MINVAL, Minimum value of an array |
| * @code{MOD}: MOD, Remainder function |
| * @code{MODULO}: MODULO, Modulo function |
| * @code{MOVE_ALLOC}: MOVE_ALLOC, Move allocation from one object to another |
| * @code{MVBITS}: MVBITS, Move bits from one integer to another |
| * @code{NEAREST}: NEAREST, Nearest representable number |
| * @code{NEW_LINE}: NEW_LINE, New line character |
| * @code{NINT}: NINT, Nearest whole number |
| * @code{NOT}: NOT, Logical negation |
| * @code{NULL}: NULL, Function that returns an disassociated pointer |
| * @code{OR}: OR, Bitwise logical OR |
| * @code{PACK}: PACK, Pack an array into an array of rank one |
| * @code{PERROR}: PERROR, Print system error message |
| * @code{PRECISION}: PRECISION, Decimal precision of a real kind |
| * @code{PRESENT}: PRESENT, Determine whether an optional dummy argument is specified |
| * @code{PRODUCT}: PRODUCT, Product of array elements |
| * @code{RADIX}: RADIX, Base of a data model |
| * @code{RANDOM_NUMBER}: RANDOM_NUMBER, Pseudo-random number |
| * @code{RANDOM_SEED}: RANDOM_SEED, Initialize a pseudo-random number sequence |
| * @code{RAND}: RAND, Real pseudo-random number |
| * @code{RANGE}: RANGE, Decimal exponent range of a real kind |
| * @code{RAN}: RAN, Real pseudo-random number |
| * @code{REAL}: REAL, Convert to real type |
| * @code{RENAME}: RENAME, Rename a file |
| * @code{REPEAT}: REPEAT, Repeated string concatenation |
| * @code{RESHAPE}: RESHAPE, Function to reshape an array |
| * @code{RRSPACING}: RRSPACING, Reciprocal of the relative spacing |
| * @code{RSHIFT}: RSHIFT, Right shift bits |
| * @code{SCALE}: SCALE, Scale a real value |
| * @code{SCAN}: SCAN, Scan a string for the presence of a set of characters |
| * @code{SECNDS}: SECNDS, Time function |
| * @code{SECOND}: SECOND, CPU time function |
| * @code{SELECTED_INT_KIND}: SELECTED_INT_KIND, Choose integer kind |
| * @code{SELECTED_REAL_KIND}: SELECTED_REAL_KIND, Choose real kind |
| * @code{SET_EXPONENT}: SET_EXPONENT, Set the exponent of the model |
| * @code{SHAPE}: SHAPE, Determine the shape of an array |
| * @code{SIGN}: SIGN, Sign copying function |
| * @code{SIGNAL}: SIGNAL, Signal handling subroutine (or function) |
| * @code{SIN}: SIN, Sine function |
| * @code{SINH}: SINH, Hyperbolic sine function |
| * @code{SIZE}: SIZE, Function to determine the size of an array |
| * @code{SLEEP}: SLEEP, Sleep for the specified number of seconds |
| * @code{SNGL}: SNGL, Convert double precision real to default real |
| * @code{SPACING}: SPACING, Smallest distance between two numbers of a given type |
| * @code{SPREAD}: SPREAD, Add a dimension to an array |
| * @code{SQRT}: SQRT, Square-root function |
| * @code{SRAND}: SRAND, Reinitialize the random number generator |
| * @code{STAT}: STAT, Get file status |
| * @code{SUM}: SUM, Sum of array elements |
| * @code{SYMLNK}: SYMLNK, Create a symbolic link |
| * @code{SYSTEM}: SYSTEM, Execute a shell command |
| * @code{SYSTEM_CLOCK}: SYSTEM_CLOCK, Time function |
| * @code{TAN}: TAN, Tangent function |
| * @code{TANH}: TANH, Hyperbolic tangent function |
| * @code{TIME}: TIME, Time function |
| * @code{TIME8}: TIME8, Time function (64-bit) |
| * @code{TINY}: TINY, Smallest positive number of a real kind |
| * @code{TRANSFER}: TRANSFER, Transfer bit patterns |
| * @code{TRANSPOSE}: TRANSPOSE, Transpose an array of rank two |
| * @code{TRIM}: TRIM, Remove trailing blank characters of a string |
| * @code{TTYNAM}: TTYNAM, Get the name of a terminal device. |
| * @code{UBOUND}: UBOUND, Upper dimension bounds of an array |
| * @code{UMASK}: UMASK, Set the file creation mask |
| * @code{UNLINK}: UNLINK, Remove a file from the file system |
| * @code{UNPACK}: UNPACK, Unpack an array of rank one into an array |
| * @code{VERIFY}: VERIFY, Scan a string for the absence of a set of characters |
| * @code{XOR}: XOR, Bitwise logical exclusive or |
| @end menu |
| |
| @node Introduction to Intrinsics |
| @section Introduction to intrinsic procedures |
| |
| The intrinsic procedures provided by GNU Fortran include all of the |
| intrinsic procedures required by the Fortran 95 standard, a set of |
| intrinsic procedures for backwards compatibility with G77, and a small |
| selection of intrinsic procedures from the Fortran 2003 standard. Any |
| conflict between a description here and a description in either the |
| Fortran 95 standard or the Fortran 2003 standard is unintentional, and |
| the standard(s) should be considered authoritative. |
| |
| The enumeration of the @code{KIND} type parameter is processor defined in |
| the Fortran 95 standard. GNU Fortran defines the default integer type and |
| default real type by @code{INTEGER(KIND=4)} and @code{REAL(KIND=4)}, |
| respectively. The standard mandates that both data types shall have |
| another kind, which have more precision. On typical target architectures |
| supported by @command{gfortran}, this kind type parameter is @code{KIND=8}. |
| Hence, @code{REAL(KIND=8)} and @code{DOUBLE PRECISION} are equivalent. |
| In the description of generic intrinsic procedures, the kind type parameter |
| will be specified by @code{KIND=*}, and in the description of specific |
| names for an intrinsic procedure the kind type parameter will be explicitly |
| given (e.g., @code{REAL(KIND=4)} or @code{REAL(KIND=8)}). Finally, for |
| brevity the optional @code{KIND=} syntax will be omitted. |
| |
| Many of the intrinsic procedures take one or more optional arguments. |
| This document follows the convention used in the Fortran 95 standard, |
| and denotes such arguments by square brackets. |
| |
| GNU Fortran offers the @option{-std=f95} and @option{-std=gnu} options, |
| which can be used to restrict the set of intrinsic procedures to a |
| given standard. By default, @command{gfortran} sets the @option{-std=gnu} |
| option, and so all intrinsic procedures described here are accepted. There |
| is one caveat. For a select group of intrinsic procedures, @command{g77} |
| implemented both a function and a subroutine. Both classes |
| have been implemented in @command{gfortran} for backwards compatibility |
| with @command{g77}. It is noted here that these functions and subroutines |
| cannot be intermixed in a given subprogram. In the descriptions that follow, |
| the applicable standard for each intrinsic procedure is noted. |
| |
| |
| |
| @node ABORT |
| @section @code{ABORT} --- Abort the program |
| @fnindex ABORT |
| @cindex program termination, with core dump |
| @cindex terminate program, with core dump |
| @cindex core, dump |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ABORT} causes immediate termination of the program. On operating |
| systems that support a core dump, @code{ABORT} will produce a core dump, |
| which is suitable for debugging purposes. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL ABORT} |
| |
| @item @emph{Return value}: |
| Does not return. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_abort |
| integer :: i = 1, j = 2 |
| if (i /= j) call abort |
| end program test_abort |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{EXIT}, @ref{KILL} |
| |
| @end table |
| |
| |
| |
| @node ABS |
| @section @code{ABS} --- Absolute value |
| @fnindex ABS |
| @fnindex CABS |
| @fnindex DABS |
| @fnindex IABS |
| @fnindex ZABS |
| @fnindex CDABS |
| @cindex absolute value |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ABS(X)} computes the absolute value of @code{X}. |
| |
| @item @emph{Standard}: |
| F77 and later, has overloads that are GNU extensions |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ABS(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be an @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and |
| kind as the argument except the return value is @code{REAL(*)} for a |
| @code{COMPLEX(*)} argument. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_abs |
| integer :: i = -1 |
| real :: x = -1.e0 |
| complex :: z = (-1.e0,0.e0) |
| i = abs(i) |
| x = abs(x) |
| x = abs(z) |
| end program test_abs |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{CABS(Z)} @tab @code{COMPLEX(4) Z} @tab @code{REAL(4)} @tab F77 and later |
| @item @code{DABS(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @item @code{IABS(I)} @tab @code{INTEGER(4) I} @tab @code{INTEGER(4)} @tab F77 and later |
| @item @code{ZABS(Z)} @tab @code{COMPLEX(8) Z} @tab @code{COMPLEX(8)} @tab GNU extension |
| @item @code{CDABS(Z)} @tab @code{COMPLEX(8) Z} @tab @code{COMPLEX(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node ACCESS |
| @section @code{ACCESS} --- Checks file access modes |
| @fnindex ACCESS |
| @cindex file system, access mode |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ACCESS(NAME, MODE)} checks whether the file @var{NAME} |
| exists, is readable, writable or executable. Except for the |
| executable check, @code{ACCESS} can be replaced by |
| Fortran 95's @code{INQUIRE}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ACCESS(NAME, MODE)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{NAME} @tab Scalar @code{CHARACTER} with the file name. |
| Tailing blank are ignored unless the character @code{achar(0)} is |
| present, then all characters up to and excluding @code{achar(0)} are |
| used as file name. |
| @item @var{MODE} @tab Scalar @code{CHARACTER} with the file access mode, |
| may be any concatenation of @code{"r"} (readable), @code{"w"} (writable) |
| and @code{"x"} (executable), or @code{" "} to check for existence. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns a scalar @code{INTEGER}, which is @code{0} if the file is |
| accessible in the given mode; otherwise or if an invalid argument |
| has been given for @code{MODE} the value @code{1} is returned. |
| |
| @item @emph{Example}: |
| @smallexample |
| program access_test |
| implicit none |
| character(len=*), parameter :: file = 'test.dat' |
| character(len=*), parameter :: file2 = 'test.dat '//achar(0) |
| if(access(file,' ') == 0) print *, trim(file),' is exists' |
| if(access(file,'r') == 0) print *, trim(file),' is readable' |
| if(access(file,'w') == 0) print *, trim(file),' is writable' |
| if(access(file,'x') == 0) print *, trim(file),' is executable' |
| if(access(file2,'rwx') == 0) & |
| print *, trim(file2),' is readable, writable and executable' |
| end program access_test |
| @end smallexample |
| @item @emph{Specific names}: |
| @item @emph{See also}: |
| |
| @end table |
| |
| |
| |
| @node ACHAR |
| @section @code{ACHAR} --- Character in @acronym{ASCII} collating sequence |
| @fnindex ACHAR |
| @cindex @acronym{ASCII} collating sequence |
| @cindex collating sequence, @acronym{ASCII} |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ACHAR(I)} returns the character located at position @code{I} |
| in the @acronym{ASCII} collating sequence. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ACHAR(I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{CHARACTER} with a length of one. The |
| kind type parameter is the same as @code{KIND('A')}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_achar |
| character c |
| c = achar(32) |
| end program test_achar |
| @end smallexample |
| |
| @item @emph{Note}: |
| See @ref{ICHAR} for a discussion of converting between numerical values |
| and formatted string representations. |
| |
| @item @emph{See also}: |
| @ref{CHAR}, @ref{IACHAR}, @ref{ICHAR} |
| |
| @end table |
| |
| |
| |
| @node ACOS |
| @section @code{ACOS} --- Arccosine function |
| @fnindex ACOS |
| @fnindex DACOS |
| @cindex trigonometric function, cosine, inverse |
| @cindex cosine, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ACOS(X)} computes the arccosine of @var{X} (inverse of @code{COS(X)}). |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ACOS(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} with a magnitude that is |
| less than one. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{ 0 \leq \acos(x) \leq \pi}. The kind type parameter |
| is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_acos |
| real(8) :: x = 0.866_8 |
| x = acos(x) |
| end program test_acos |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DACOS(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{COS} |
| |
| @end table |
| |
| |
| |
| @node ACOSH |
| @section @code{ACOSH} --- Hyperbolic arccosine function |
| @fnindex ACOSH |
| @fnindex DACOSH |
| @cindex area hyperbolic cosine |
| @cindex hyperbolic arccosine |
| @cindex hyperbolic function, cosine, inverse |
| @cindex cosine, hyperbolic, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ACOSH(X)} computes the hyperbolic arccosine of @var{X} (inverse of |
| @code{COSH(X)}). |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ACOSH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} with a magnitude that is |
| greater or equal to one. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{0 \leq \acosh (x) \leq \infty}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_acosh |
| REAL(8), DIMENSION(3) :: x = (/ 1.0, 2.0, 3.0 /) |
| WRITE (*,*) ACOSH(x) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DACOSH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{COSH} |
| @end table |
| |
| |
| |
| @node ADJUSTL |
| @section @code{ADJUSTL} --- Left adjust a string |
| @fnindex ADJUSTL |
| @cindex string, adjust left |
| @cindex adjust string |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ADJUSTL(STR)} will left adjust a string by removing leading spaces. |
| Spaces are inserted at the end of the string as needed. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ADJUSTL(STR)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STR} @tab The type shall be @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{CHARACTER} where leading spaces |
| are removed and the same number of spaces are inserted on the end |
| of @var{STR}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_adjustl |
| character(len=20) :: str = ' gfortran' |
| str = adjustl(str) |
| print *, str |
| end program test_adjustl |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ADJUSTR}, @ref{TRIM} |
| @end table |
| |
| |
| |
| @node ADJUSTR |
| @section @code{ADJUSTR} --- Right adjust a string |
| @fnindex ADJUSTR |
| @cindex string, adjust right |
| @cindex adjust string |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ADJUSTR(STR)} will right adjust a string by removing trailing spaces. |
| Spaces are inserted at the start of the string as needed. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ADJUSTR(STR)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STR} @tab The type shall be @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{CHARACTER} where trailing spaces |
| are removed and the same number of spaces are inserted at the start |
| of @var{STR}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_adjustr |
| character(len=20) :: str = 'gfortran' |
| str = adjustr(str) |
| print *, str |
| end program test_adjustr |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ADJUSTL}, @ref{TRIM} |
| @end table |
| |
| |
| |
| @node AIMAG |
| @section @code{AIMAG} --- Imaginary part of complex number |
| @fnindex AIMAG |
| @fnindex DIMAG |
| @fnindex IMAG |
| @fnindex IMAGPART |
| @cindex complex numbers, imaginary part |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{AIMAG(Z)} yields the imaginary part of complex argument @code{Z}. |
| The @code{IMAG(Z)} and @code{IMAGPART(Z)} intrinsic functions are provided |
| for compatibility with @command{g77}, and their use in new code is |
| strongly discouraged. |
| |
| @item @emph{Standard}: |
| F77 and later, has overloads that are GNU extensions |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = AIMAG(Z)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{Z} @tab The type of the argument shall be @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type real with the |
| kind type parameter of the argument. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_aimag |
| complex(4) z4 |
| complex(8) z8 |
| z4 = cmplx(1.e0_4, 0.e0_4) |
| z8 = cmplx(0.e0_8, 1.e0_8) |
| print *, aimag(z4), dimag(z8) |
| end program test_aimag |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DIMAG(Z)} @tab @code{COMPLEX(8) Z} @tab @code{REAL(8)} @tab GNU extension |
| @item @code{IMAG(Z)} @tab @code{COMPLEX(*) Z} @tab @code{REAL(*)} @tab GNU extension |
| @item @code{IMAGPART(Z)} @tab @code{COMPLEX(*) Z} @tab @code{REAL(*)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node AINT |
| @section @code{AINT} --- Truncate to a whole number |
| @fnindex AINT |
| @fnindex DINT |
| @cindex floor |
| @cindex rounding, floor |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{AINT(X [, KIND])} truncates its argument to a whole number. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = AINT(X [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be @code{REAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type real with the kind type parameter of the |
| argument if the optional @var{KIND} is absent; otherwise, the kind |
| type parameter will be given by @var{KIND}. If the magnitude of |
| @var{X} is less than one, then @code{AINT(X)} returns zero. If the |
| magnitude is equal to or greater than one, then it returns the largest |
| whole number that does not exceed its magnitude. The sign is the same |
| as the sign of @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_aint |
| real(4) x4 |
| real(8) x8 |
| x4 = 1.234E0_4 |
| x8 = 4.321_8 |
| print *, aint(x4), dint(x8) |
| x8 = aint(x4,8) |
| end program test_aint |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DINT(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node ALARM |
| @section @code{ALARM} --- Execute a routine after a given delay |
| @fnindex ALARM |
| @cindex delayed execution |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ALARM(SECONDS, HANDLER [, STATUS])} causes external subroutine @var{HANDLER} |
| to be executed after a delay of @var{SECONDS} by using @code{alarm(2)} to |
| set up a signal and @code{signal(2)} to catch it. If @var{STATUS} is |
| supplied, it will be returned with the number of seconds remaining until |
| any previously scheduled alarm was due to be delivered, or zero if there |
| was no previously scheduled alarm. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL ALARM(SECONDS, HANDLER [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SECONDS} @tab The type of the argument shall be a scalar |
| @code{INTEGER}. It is @code{INTENT(IN)}. |
| @item @var{HANDLER} @tab Signal handler (@code{INTEGER FUNCTION} or |
| @code{SUBROUTINE}) or dummy/global @code{INTEGER} scalar. The scalar |
| values may be either @code{SIG_IGN=1} to ignore the alarm generated |
| or @code{SIG_DFL=0} to set the default action. It is @code{INTENT(IN)}. |
| @item @var{STATUS} @tab (Optional) @var{STATUS} shall be a scalar |
| variable of the default @code{INTEGER} kind. It is @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_alarm |
| external handler_print |
| integer i |
| call alarm (3, handler_print, i) |
| print *, i |
| call sleep(10) |
| end program test_alarm |
| @end smallexample |
| This will cause the external routine @var{handler_print} to be called |
| after 3 seconds. |
| @end table |
| |
| |
| |
| @node ALL |
| @section @code{ALL} --- All values in @var{MASK} along @var{DIM} are true |
| @fnindex ALL |
| @cindex array, apply condition |
| @cindex array, condition testing |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ALL(MASK [, DIM])} determines if all the values are true in @var{MASK} |
| in the array along dimension @var{DIM}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ALL(MASK [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MASK} @tab The type of the argument shall be @code{LOGICAL(*)} and |
| it shall not be scalar. |
| @item @var{DIM} @tab (Optional) @var{DIM} shall be a scalar integer |
| with a value that lies between one and the rank of @var{MASK}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| @code{ALL(MASK)} returns a scalar value of type @code{LOGICAL(*)} where |
| the kind type parameter is the same as the kind type parameter of |
| @var{MASK}. If @var{DIM} is present, then @code{ALL(MASK, DIM)} returns |
| an array with the rank of @var{MASK} minus 1. The shape is determined from |
| the shape of @var{MASK} where the @var{DIM} dimension is elided. |
| |
| @table @asis |
| @item (A) |
| @code{ALL(MASK)} is true if all elements of @var{MASK} are true. |
| It also is true if @var{MASK} has zero size; otherwise, it is false. |
| @item (B) |
| If the rank of @var{MASK} is one, then @code{ALL(MASK,DIM)} is equivalent |
| to @code{ALL(MASK)}. If the rank is greater than one, then @code{ALL(MASK,DIM)} |
| is determined by applying @code{ALL} to the array sections. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_all |
| logical l |
| l = all((/.true., .true., .true./)) |
| print *, l |
| call section |
| contains |
| subroutine section |
| integer a(2,3), b(2,3) |
| a = 1 |
| b = 1 |
| b(2,2) = 2 |
| print *, all(a .eq. b, 1) |
| print *, all(a .eq. b, 2) |
| end subroutine section |
| end program test_all |
| @end smallexample |
| @end table |
| |
| |
| |
| @node ALLOCATED |
| @section @code{ALLOCATED} --- Status of an allocatable entity |
| @fnindex ALLOCATED |
| @cindex allocation, status |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ALLOCATED(X)} checks the status of whether @var{X} is allocated. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ALLOCATED(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The argument shall be an @code{ALLOCATABLE} array. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar @code{LOGICAL} with the default logical |
| kind type parameter. If @var{X} is allocated, @code{ALLOCATED(X)} |
| is @code{.TRUE.}; otherwise, it returns the @code{.TRUE.} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_allocated |
| integer :: i = 4 |
| real(4), allocatable :: x(:) |
| if (allocated(x) .eqv. .false.) allocate(x(i)) |
| end program test_allocated |
| @end smallexample |
| @end table |
| |
| |
| |
| @node AND |
| @section @code{AND} --- Bitwise logical AND |
| @fnindex AND |
| @cindex bitwise logical and |
| @cindex logical and, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| Bitwise logical @code{AND}. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. For integer arguments, programmers should consider |
| the use of the @ref{IAND} intrinsic defined by the Fortran standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = AND(I, J)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @item @var{J} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is either @code{INTEGER(*)} or @code{LOGICAL} after |
| cross-promotion of the arguments. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_and |
| LOGICAL :: T = .TRUE., F = .FALSE. |
| INTEGER :: a, b |
| DATA a / Z'F' /, b / Z'3' / |
| |
| WRITE (*,*) AND(T, T), AND(T, F), AND(F, T), AND(F, F) |
| WRITE (*,*) AND(a, b) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| F95 elemental function: @ref{IAND} |
| @end table |
| |
| |
| |
| @node ANINT |
| @section @code{ANINT} --- Nearest whole number |
| @fnindex ANINT |
| @fnindex DNINT |
| @cindex ceiling |
| @cindex rounding, ceiling |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ANINT(X [, KIND])} rounds its argument to the nearest whole number. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ANINT(X [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be @code{REAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type real with the kind type parameter of the |
| argument if the optional @var{KIND} is absent; otherwise, the kind |
| type parameter will be given by @var{KIND}. If @var{X} is greater than |
| zero, then @code{ANINT(X)} returns @code{AINT(X+0.5)}. If @var{X} is |
| less than or equal to zero, then it returns @code{AINT(X-0.5)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_anint |
| real(4) x4 |
| real(8) x8 |
| x4 = 1.234E0_4 |
| x8 = 4.321_8 |
| print *, anint(x4), dnint(x8) |
| x8 = anint(x4,8) |
| end program test_anint |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DNINT(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node ANY |
| @section @code{ANY} --- Any value in @var{MASK} along @var{DIM} is true |
| @fnindex ANY |
| @cindex array, apply condition |
| @cindex array, condition testing |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ANY(MASK [, DIM])} determines if any of the values in the logical array |
| @var{MASK} along dimension @var{DIM} are @code{.TRUE.}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ANY(MASK [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MASK} @tab The type of the argument shall be @code{LOGICAL(*)} and |
| it shall not be scalar. |
| @item @var{DIM} @tab (Optional) @var{DIM} shall be a scalar integer |
| with a value that lies between one and the rank of @var{MASK}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| @code{ANY(MASK)} returns a scalar value of type @code{LOGICAL(*)} where |
| the kind type parameter is the same as the kind type parameter of |
| @var{MASK}. If @var{DIM} is present, then @code{ANY(MASK, DIM)} returns |
| an array with the rank of @var{MASK} minus 1. The shape is determined from |
| the shape of @var{MASK} where the @var{DIM} dimension is elided. |
| |
| @table @asis |
| @item (A) |
| @code{ANY(MASK)} is true if any element of @var{MASK} is true; |
| otherwise, it is false. It also is false if @var{MASK} has zero size. |
| @item (B) |
| If the rank of @var{MASK} is one, then @code{ANY(MASK,DIM)} is equivalent |
| to @code{ANY(MASK)}. If the rank is greater than one, then @code{ANY(MASK,DIM)} |
| is determined by applying @code{ANY} to the array sections. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_any |
| logical l |
| l = any((/.true., .true., .true./)) |
| print *, l |
| call section |
| contains |
| subroutine section |
| integer a(2,3), b(2,3) |
| a = 1 |
| b = 1 |
| b(2,2) = 2 |
| print *, any(a .eq. b, 1) |
| print *, any(a .eq. b, 2) |
| end subroutine section |
| end program test_any |
| @end smallexample |
| @end table |
| |
| |
| |
| @node ASIN |
| @section @code{ASIN} --- Arcsine function |
| @fnindex ASIN |
| @fnindex DASIN |
| @cindex trigonometric function, sine, inverse |
| @cindex sine, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ASIN(X)} computes the arcsine of its @var{X} (inverse of @code{SIN(X)}). |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ASIN(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and a magnitude that is |
| less than one. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{-\pi / 2 \leq \asin (x) \leq \pi / 2}. The kind type |
| parameter is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_asin |
| real(8) :: x = 0.866_8 |
| x = asin(x) |
| end program test_asin |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DASIN(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{SIN} |
| |
| @end table |
| |
| |
| |
| @node ASINH |
| @section @code{ASINH} --- Hyperbolic arcsine function |
| @fnindex ASINH |
| @fnindex DASINH |
| @cindex area hyperbolic sine |
| @cindex hyperbolic arcsine |
| @cindex hyperbolic function, sine, inverse |
| @cindex sine, hyperbolic, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ASINH(X)} computes the hyperbolic arcsine of @var{X} (inverse of @code{SINH(X)}). |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ASINH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, with @var{X} a real number. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{-\infty \leq \asinh (x) \leq \infty}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_asinh |
| REAL(8), DIMENSION(3) :: x = (/ -1.0, 0.0, 1.0 /) |
| WRITE (*,*) ASINH(x) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DASINH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension. |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{SINH} |
| @end table |
| |
| |
| |
| @node ASSOCIATED |
| @section @code{ASSOCIATED} --- Status of a pointer or pointer/target pair |
| @fnindex ASSOCIATED |
| @cindex pointer, status |
| @cindex association status |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ASSOCIATED(PTR [, TGT])} determines the status of the pointer @var{PTR} |
| or if @var{PTR} is associated with the target @var{TGT}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ASSOCIATED(PTR [, TGT])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PTR} @tab @var{PTR} shall have the @code{POINTER} attribute and |
| it can be of any type. |
| @item @var{TGT} @tab (Optional) @var{TGT} shall be a @code{POINTER} or |
| a @code{TARGET}. It must have the same type, kind type parameter, and |
| array rank as @var{PTR}. |
| @end multitable |
| The status of neither @var{PTR} nor @var{TGT} can be undefined. |
| |
| @item @emph{Return value}: |
| @code{ASSOCIATED(PTR)} returns a scalar value of type @code{LOGICAL(4)}. |
| There are several cases: |
| @table @asis |
| @item (A) If the optional @var{TGT} is not present, then @code{ASSOCIATED(PTR)} |
| is true if @var{PTR} is associated with a target; otherwise, it returns false. |
| @item (B) If @var{TGT} is present and a scalar target, the result is true if |
| @var{TGT} |
| is not a 0 sized storage sequence and the target associated with @var{PTR} |
| occupies the same storage units. If @var{PTR} is disassociated, then the |
| result is false. |
| @item (C) If @var{TGT} is present and an array target, the result is true if |
| @var{TGT} and @var{PTR} have the same shape, are not 0 sized arrays, are |
| arrays whose elements are not 0 sized storage sequences, and @var{TGT} and |
| @var{PTR} occupy the same storage units in array element order. |
| As in case(B), the result is false, if @var{PTR} is disassociated. |
| @item (D) If @var{TGT} is present and an scalar pointer, the result is true if |
| target associated with @var{PTR} and the target associated with @var{TGT} |
| are not 0 sized storage sequences and occupy the same storage units. |
| The result is false, if either @var{TGT} or @var{PTR} is disassociated. |
| @item (E) If @var{TGT} is present and an array pointer, the result is true if |
| target associated with @var{PTR} and the target associated with @var{TGT} |
| have the same shape, are not 0 sized arrays, are arrays whose elements are |
| not 0 sized storage sequences, and @var{TGT} and @var{PTR} occupy the same |
| storage units in array element order. |
| The result is false, if either @var{TGT} or @var{PTR} is disassociated. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_associated |
| implicit none |
| real, target :: tgt(2) = (/1., 2./) |
| real, pointer :: ptr(:) |
| ptr => tgt |
| if (associated(ptr) .eqv. .false.) call abort |
| if (associated(ptr,tgt) .eqv. .false.) call abort |
| end program test_associated |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{NULL} |
| @end table |
| |
| |
| |
| @node ATAN |
| @section @code{ATAN} --- Arctangent function |
| @fnindex ATAN |
| @fnindex DATAN |
| @cindex trigonometric function, tangent, inverse |
| @cindex tangent, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ATAN(X)} computes the arctangent of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ATAN(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{ - \pi / 2 \leq \atan (x) \leq \pi / 2}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_atan |
| real(8) :: x = 2.866_8 |
| x = atan(x) |
| end program test_atan |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DATAN(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{TAN} |
| |
| @end table |
| |
| |
| |
| @node ATAN2 |
| @section @code{ATAN2} --- Arctangent function |
| @fnindex ATAN2 |
| @fnindex DATAN2 |
| @cindex trigonometric function, tangent, inverse |
| @cindex tangent, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ATAN2(Y,X)} computes the arctangent of the complex number |
| @math{X + i Y}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ATAN2(Y,X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{Y} @tab The type shall be @code{REAL(*)}. |
| @item @var{X} @tab The type and kind type parameter shall be the same as @var{Y}. |
| If @var{Y} is zero, then @var{X} must be nonzero. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value has the same type and kind type parameter as @var{Y}. |
| It is the principal value of the complex number @math{X + i Y}. If |
| @var{X} is nonzero, then it lies in the range @math{-\pi \le \atan (x) \leq \pi}. |
| The sign is positive if @var{Y} is positive. If @var{Y} is zero, then |
| the return value is zero if @var{X} is positive and @math{\pi} if @var{X} |
| is negative. Finally, if @var{X} is zero, then the magnitude of the result |
| is @math{\pi/2}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_atan2 |
| real(4) :: x = 1.e0_4, y = 0.5e0_4 |
| x = atan2(y,x) |
| end program test_atan2 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DATAN2(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node ATANH |
| @section @code{ATANH} --- Hyperbolic arctangent function |
| @fnindex ASINH |
| @fnindex DASINH |
| @cindex area hyperbolic tangent |
| @cindex hyperbolic arctangent |
| @cindex hyperbolic function, tangent, inverse |
| @cindex tangent, hyperbolic, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ATANH(X)} computes the hyperbolic arctangent of @var{X} (inverse |
| of @code{TANH(X)}). |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ATANH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} with a magnitude |
| that is less than or equal to one. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{-\infty \leq \atanh(x) \leq \infty}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_atanh |
| REAL, DIMENSION(3) :: x = (/ -1.0, 0.0, 1.0 /) |
| WRITE (*,*) ATANH(x) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DATANH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{TANH} |
| @end table |
| |
| |
| |
| @node BESJ0 |
| @section @code{BESJ0} --- Bessel function of the first kind of order 0 |
| @fnindex BESJ0 |
| @fnindex DBESJ0 |
| @cindex Bessel function, first kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESJ0(X)} computes the Bessel function of the first kind of order 0 |
| of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESJ0(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{ - 0.4027... \leq Bessel (0,x) \leq 1}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besj0 |
| real(8) :: x = 0.0_8 |
| x = besj0(x) |
| end program test_besj0 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESJ0(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node BESJ1 |
| @section @code{BESJ1} --- Bessel function of the first kind of order 1 |
| @fnindex BESJ1 |
| @fnindex DBESJ1 |
| @cindex Bessel function, first kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESJ1(X)} computes the Bessel function of the first kind of order 1 |
| of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESJ1(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{ - 0.5818... \leq Bessel (0,x) \leq 0.5818 }. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besj1 |
| real(8) :: x = 1.0_8 |
| x = besj1(x) |
| end program test_besj1 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESJ1(X)}@tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node BESJN |
| @section @code{BESJN} --- Bessel function of the first kind |
| @fnindex BESJN |
| @fnindex DBESJN |
| @cindex Bessel function, first kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESJN(N, X)} computes the Bessel function of the first kind of order |
| @var{N} of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESJN(N, X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{N} @tab The type shall be @code{INTEGER(*)}, and it shall be scalar. |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besjn |
| real(8) :: x = 1.0_8 |
| x = besjn(5,x) |
| end program test_besjn |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESJN(X)} @tab @code{INTEGER(*) N} @tab @code{REAL(8)} @tab GNU extension |
| @item @tab @code{REAL(8) X} @tab @tab |
| @end multitable |
| @end table |
| |
| |
| |
| @node BESY0 |
| @section @code{BESY0} --- Bessel function of the second kind of order 0 |
| @fnindex BESY0 |
| @fnindex DBESY0 |
| @cindex Bessel function, second kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESY0(X)} computes the Bessel function of the second kind of order 0 |
| of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESY0(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besy0 |
| real(8) :: x = 0.0_8 |
| x = besy0(x) |
| end program test_besy0 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESY0(X)}@tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node BESY1 |
| @section @code{BESY1} --- Bessel function of the second kind of order 1 |
| @fnindex BESY1 |
| @fnindex DBESY1 |
| @cindex Bessel function, second kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESY1(X)} computes the Bessel function of the second kind of order 1 |
| of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESY1(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besy1 |
| real(8) :: x = 1.0_8 |
| x = besy1(x) |
| end program test_besy1 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESY1(X)}@tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node BESYN |
| @section @code{BESYN} --- Bessel function of the second kind |
| @fnindex BESYN |
| @fnindex DBESYN |
| @cindex Bessel function, second kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BESYN(N, X)} computes the Bessel function of the second kind of order |
| @var{N} of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BESYN(N, X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{N} @tab The type shall be @code{INTEGER(*)}, and it shall be scalar. |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_besyn |
| real(8) :: x = 1.0_8 |
| x = besyn(5,x) |
| end program test_besyn |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DBESYN(N,X)} @tab @code{INTEGER(*) N} @tab @code{REAL(8)} @tab GNU extension |
| @item @tab @code{REAL(8) X} @tab @tab |
| @end multitable |
| @end table |
| |
| |
| |
| @node BIT_SIZE |
| @section @code{BIT_SIZE} --- Bit size inquiry function |
| @fnindex BIT_SIZE |
| @cindex bits, number of |
| @cindex size of a variable, in bits |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BIT_SIZE(I)} returns the number of bits (integer precision plus sign bit) |
| represented by the type of @var{I}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BIT_SIZE(I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_bit_size |
| integer :: i = 123 |
| integer :: size |
| size = bit_size(i) |
| print *, size |
| end program test_bit_size |
| @end smallexample |
| @end table |
| |
| |
| |
| @node BTEST |
| @section @code{BTEST} --- Bit test function |
| @fnindex BTEST |
| @cindex bits, testing |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{BTEST(I,POS)} returns logical @code{.TRUE.} if the bit at @var{POS} |
| in @var{I} is set. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = BTEST(I, POS)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{POS} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{LOGICAL} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_btest |
| integer :: i = 32768 + 1024 + 64 |
| integer :: pos |
| logical :: bool |
| do pos=0,16 |
| bool = btest(i, pos) |
| print *, pos, bool |
| end do |
| end program test_btest |
| @end smallexample |
| @end table |
| |
| |
| |
| @node CEILING |
| @section @code{CEILING} --- Integer ceiling function |
| @fnindex CEILING |
| @cindex ceiling |
| @cindex rounding, ceiling |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CEILING(X)} returns the least integer greater than or equal to @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = CEILING(X [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(KIND)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_ceiling |
| real :: x = 63.29 |
| real :: y = -63.59 |
| print *, ceiling(x) ! returns 64 |
| print *, ceiling(y) ! returns -63 |
| end program test_ceiling |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FLOOR}, @ref{NINT} |
| |
| @end table |
| |
| |
| |
| @node CHAR |
| @section @code{CHAR} --- Character conversion function |
| @fnindex CHAR |
| @cindex conversion, to character |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CHAR(I [, KIND])} returns the character represented by the integer @var{I}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = CHAR(I [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{CHARACTER(1)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_char |
| integer :: i = 74 |
| character(1) :: c |
| c = char(i) |
| print *, i, c ! returns 'J' |
| end program test_char |
| @end smallexample |
| |
| @item @emph{Note}: |
| See @ref{ICHAR} for a discussion of converting between numerical values |
| and formatted string representations. |
| |
| @item @emph{See also}: |
| @ref{ACHAR}, @ref{IACHAR}, @ref{ICHAR} |
| |
| @end table |
| |
| |
| |
| @node CHDIR |
| @section @code{CHDIR} --- Change working directory |
| @fnindex CHDIR |
| @cindex system, working directory |
| |
| @table @asis |
| @item @emph{Description}: |
| Change current working directory to a specified path. |
| |
| This intrinsic is provided in both subroutine and function forms; however, |
| only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL CHDIR(NAME [, STATUS])} |
| @item @code{STATUS = CHDIR(NAME)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{NAME} @tab The type shall be @code{CHARACTER(*)} and shall |
| specify a valid path within the file system. |
| @item @var{STATUS} @tab (Optional) @code{INTEGER} status flag of the default |
| kind. Returns 0 on success, and a system specific |
| and non-zero error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_chdir |
| CHARACTER(len=255) :: path |
| CALL getcwd(path) |
| WRITE(*,*) TRIM(path) |
| CALL chdir("/tmp") |
| CALL getcwd(path) |
| WRITE(*,*) TRIM(path) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GETCWD} |
| @end table |
| |
| |
| |
| @node CHMOD |
| @section @code{CHMOD} --- Change access permissions of files |
| @fnindex CHMOD |
| @cindex file system, change access mode |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CHMOD} changes the permissions of a file. This function invokes |
| @code{/bin/chmod} and might therefore not work on all platforms. |
| |
| This intrinsic is provided in both subroutine and function forms; however, |
| only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL CHMOD(NAME, MODE[, STATUS])} |
| @item @code{STATUS = CHMOD(NAME, MODE)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{NAME} @tab Scalar @code{CHARACTER} with the file name. |
| Trailing blanks are ignored unless the character @code{achar(0)} is |
| present, then all characters up to and excluding @code{achar(0)} are |
| used as the file name. |
| |
| @item @var{MODE} @tab Scalar @code{CHARACTER} giving the file permission. |
| @var{MODE} uses the same syntax as the @var{MODE} argument of |
| @code{/bin/chmod}. |
| |
| @item @var{STATUS} @tab (optional) scalar @code{INTEGER}, which is |
| @code{0} on success and non-zero otherwise. |
| @end multitable |
| |
| @item @emph{Return value}: |
| In either syntax, @var{STATUS} is set to @code{0} on success and non-zero |
| otherwise. |
| |
| @item @emph{Example}: |
| @code{CHMOD} as subroutine |
| @smallexample |
| program chmod_test |
| implicit none |
| integer :: status |
| call chmod('test.dat','u+x',status) |
| print *, 'Status: ', status |
| end program chmod_test |
| @end smallexample |
| @code{CHMOD} as non-elemental function: |
| @smallexample |
| program chmod_test |
| implicit none |
| integer :: status |
| status = chmod('test.dat','u+x') |
| print *, 'Status: ', status |
| end program chmod_test |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node CMPLX |
| @section @code{CMPLX} --- Complex conversion function |
| @fnindex CMPLX |
| @cindex complex numbers, conversion to |
| @cindex conversion, to complex |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CMPLX(X [, Y [, KIND]])} returns a complex number where @var{X} is converted to |
| the real component. If @var{Y} is present it is converted to the imaginary |
| component. If @var{Y} is not present then the imaginary component is set to |
| 0.0. If @var{X} is complex then @var{Y} must not be present. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = CMPLX(X [, Y [, KIND]])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type may be @code{INTEGER(*)}, @code{REAL(*)}, |
| or @code{COMPLEX(*)}. |
| @item @var{Y} @tab (Optional; only allowed if @var{X} is not |
| @code{COMPLEX(*)}.) May be @code{INTEGER(*)} |
| or @code{REAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{COMPLEX(*)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_cmplx |
| integer :: i = 42 |
| real :: x = 3.14 |
| complex :: z |
| z = cmplx(i, x) |
| print *, z, cmplx(x) |
| end program test_cmplx |
| @end smallexample |
| @end table |
| |
| |
| |
| @node COMMAND_ARGUMENT_COUNT |
| @section @code{COMMAND_ARGUMENT_COUNT} --- Get number of command line arguments |
| @fnindex COMMAND_ARGUMENT_COUNT |
| @cindex command-line arguments |
| @cindex command-line arguments, number of |
| @cindex arguments, to program |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{COMMAND_ARGUMENT_COUNT()} returns the number of arguments passed on the |
| command line when the containing program was invoked. |
| |
| @item @emph{Standard}: |
| F2003 |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = COMMAND_ARGUMENT_COUNT()} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item None |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(4)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_command_argument_count |
| integer :: count |
| count = command_argument_count() |
| print *, count |
| end program test_command_argument_count |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GET_COMMAND}, @ref{GET_COMMAND_ARGUMENT} |
| @end table |
| |
| |
| |
| @node CONJG |
| @section @code{CONJG} --- Complex conjugate function |
| @fnindex CONJG |
| @fnindex DCONJG |
| @cindex complex conjugate |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CONJG(Z)} returns the conjugate of @var{Z}. If @var{Z} is @code{(x, y)} |
| then the result is @code{(x, -y)} |
| |
| @item @emph{Standard}: |
| F77 and later, has overloads that are GNU extensions |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{Z = CONJG(Z)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{Z} @tab The type shall be @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{COMPLEX(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_conjg |
| complex :: z = (2.0, 3.0) |
| complex(8) :: dz = (2.71_8, -3.14_8) |
| z= conjg(z) |
| print *, z |
| dz = dconjg(dz) |
| print *, dz |
| end program test_conjg |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DCONJG(Z)} @tab @code{COMPLEX(8) Z} @tab @code{COMPLEX(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node COS |
| @section @code{COS} --- Cosine function |
| @fnindex COS |
| @fnindex DCOS |
| @fnindex CCOS |
| @fnindex ZCOS |
| @fnindex CDCOS |
| @cindex trigonometric function, cosine |
| @cindex cosine |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{COS(X)} computes the cosine of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later, has overloads that are GNU extensions |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = COS(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} or |
| @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it lies in the |
| range @math{ -1 \leq \cos (x) \leq 1}. The kind type |
| parameter is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_cos |
| real :: x = 0.0 |
| x = cos(x) |
| end program test_cos |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DCOS(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @item @code{CCOS(X)} @tab @code{COMPLEX(4) X} @tab @code{COMPLEX(4)} @tab F77 and later |
| @item @code{ZCOS(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @item @code{CDCOS(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{ACOS} |
| |
| @end table |
| |
| |
| |
| @node COSH |
| @section @code{COSH} --- Hyperbolic cosine function |
| @fnindex COSH |
| @fnindex DCOSH |
| @cindex hyperbolic cosine |
| @cindex hyperbolic function, cosine |
| @cindex cosine, hyperbolic |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{COSH(X)} computes the hyperbolic cosine of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{X = COSH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and it is positive |
| (@math{ \cosh (x) \geq 0 }. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_cosh |
| real(8) :: x = 1.0_8 |
| x = cosh(x) |
| end program test_cosh |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DCOSH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| Inverse function: @ref{ACOSH} |
| |
| @end table |
| |
| |
| |
| @node COUNT |
| @section @code{COUNT} --- Count function |
| @fnindex COUNT |
| @cindex array, conditionally count elements |
| @cindex array, element counting |
| @cindex array, number of elements |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{COUNT(MASK [, DIM])} counts the number of @code{.TRUE.} elements of |
| @var{MASK} along the dimension of @var{DIM}. If @var{DIM} is omitted it is |
| taken to be @code{1}. @var{DIM} is a scaler of type @code{INTEGER} in the |
| range of @math{1 /leq DIM /leq n)} where @math{n} is the rank of @var{MASK}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = COUNT(MASK [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MASK} @tab The type shall be @code{LOGICAL}. |
| @item @var{DIM} @tab The type shall be @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} with rank equal to that of |
| @var{MASK}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_count |
| integer, dimension(2,3) :: a, b |
| logical, dimension(2,3) :: mask |
| a = reshape( (/ 1, 2, 3, 4, 5, 6 /), (/ 2, 3 /)) |
| b = reshape( (/ 0, 7, 3, 4, 5, 8 /), (/ 2, 3 /)) |
| print '(3i3)', a(1,:) |
| print '(3i3)', a(2,:) |
| print * |
| print '(3i3)', b(1,:) |
| print '(3i3)', b(2,:) |
| print * |
| mask = a.ne.b |
| print '(3l3)', mask(1,:) |
| print '(3l3)', mask(2,:) |
| print * |
| print '(3i3)', count(mask) |
| print * |
| print '(3i3)', count(mask, 1) |
| print * |
| print '(3i3)', count(mask, 2) |
| end program test_count |
| @end smallexample |
| @end table |
| |
| |
| |
| @node CPU_TIME |
| @section @code{CPU_TIME} --- CPU elapsed time in seconds |
| @fnindex CPU_TIME |
| @cindex time, elapsed |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns a @code{REAL(*)} value representing the elapsed CPU time in |
| seconds. This is useful for testing segments of code to determine |
| execution time. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL CPU_TIME(TIME)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TIME} @tab The type shall be @code{REAL(*)} with @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| None |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_cpu_time |
| real :: start, finish |
| call cpu_time(start) |
| ! put code to test here |
| call cpu_time(finish) |
| print '("Time = ",f6.3," seconds.")',finish-start |
| end program test_cpu_time |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SYSTEM_CLOCK}, @ref{DATE_AND_TIME} |
| @end table |
| |
| |
| |
| @node CSHIFT |
| @section @code{CSHIFT} --- Circular shift elements of an array |
| @fnindex CSHIFT |
| @cindex array, shift circularly |
| @cindex array, permutation |
| @cindex array, rotate |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CSHIFT(ARRAY, SHIFT [, DIM])} performs a circular shift on elements of |
| @var{ARRAY} along the dimension of @var{DIM}. If @var{DIM} is omitted it is |
| taken to be @code{1}. @var{DIM} is a scaler of type @code{INTEGER} in the |
| range of @math{1 /leq DIM /leq n)} where @math{n} is the rank of @var{ARRAY}. |
| If the rank of @var{ARRAY} is one, then all elements of @var{ARRAY} are shifted |
| by @var{SHIFT} places. If rank is greater than one, then all complete rank one |
| sections of @var{ARRAY} along the given dimension are shifted. Elements |
| shifted out one end of each rank one section are shifted back in the other end. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = CSHIFT(A, SHIFT [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab May be any type, not scaler. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER}. |
| @item @var{DIM} @tab The type shall be @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns an array of same type and rank as the @var{ARRAY} argument. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_cshift |
| integer, dimension(3,3) :: a |
| a = reshape( (/ 1, 2, 3, 4, 5, 6, 7, 8, 9 /), (/ 3, 3 /)) |
| print '(3i3)', a(1,:) |
| print '(3i3)', a(2,:) |
| print '(3i3)', a(3,:) |
| a = cshift(a, SHIFT=(/1, 2, -1/), DIM=2) |
| print * |
| print '(3i3)', a(1,:) |
| print '(3i3)', a(2,:) |
| print '(3i3)', a(3,:) |
| end program test_cshift |
| @end smallexample |
| @end table |
| |
| |
| |
| @node CTIME |
| @section @code{CTIME} --- Convert a time into a string |
| @fnindex CTIME |
| @cindex time, conversion to string |
| @cindex conversion, to string |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{CTIME} converts a system time value, such as returned by |
| @code{TIME8()}, to a string of the form @samp{Sat Aug 19 18:13:14 1995}. |
| |
| This intrinsic is provided in both subroutine and function forms; however, |
| only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL CTIME(TIME, RESULT)}. |
| @item @code{RESULT = CTIME(TIME)}, (not recommended). |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TIME} @tab The type shall be of type @code{INTEGER(KIND=8)}. |
| @item @var{RESULT} @tab The type shall be of type @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The converted date and time as a string. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_ctime |
| integer(8) :: i |
| character(len=30) :: date |
| i = time8() |
| |
| ! Do something, main part of the program |
| |
| call ctime(i,date) |
| print *, 'Program was started on ', date |
| end program test_ctime |
| @end smallexample |
| |
| @item @emph{See Also}: |
| @ref{GMTIME}, @ref{LTIME}, @ref{TIME}, @ref{TIME8} |
| @end table |
| |
| |
| |
| @node DATE_AND_TIME |
| @section @code{DATE_AND_TIME} --- Date and time subroutine |
| @fnindex DATE_AND_TIME |
| @cindex date, current |
| @cindex current date |
| @cindex time, current |
| @cindex current time |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DATE_AND_TIME(DATE, TIME, ZONE, VALUES)} gets the corresponding date and |
| time information from the real-time system clock. @var{DATE} is |
| @code{INTENT(OUT)} and has form ccyymmdd. @var{TIME} is @code{INTENT(OUT)} and |
| has form hhmmss.sss. @var{ZONE} is @code{INTENT(OUT)} and has form (+-)hhmm, |
| representing the difference with respect to Coordinated Universal Time (UTC). |
| Unavailable time and date parameters return blanks. |
| |
| @var{VALUES} is @code{INTENT(OUT)} and provides the following: |
| |
| @multitable @columnfractions .15 .30 .40 |
| @item @tab @code{VALUE(1)}: @tab The year |
| @item @tab @code{VALUE(2)}: @tab The month |
| @item @tab @code{VALUE(3)}: @tab The day of the month |
| @item @tab @code{VALUE(4)}: @tab Time difference with UTC in minutes |
| @item @tab @code{VALUE(5)}: @tab The hour of the day |
| @item @tab @code{VALUE(6)}: @tab The minutes of the hour |
| @item @tab @code{VALUE(7)}: @tab The seconds of the minute |
| @item @tab @code{VALUE(8)}: @tab The milliseconds of the second |
| @end multitable |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL DATE_AND_TIME([DATE, TIME, ZONE, VALUES])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{DATE} @tab (Optional) The type shall be @code{CHARACTER(8)} or larger. |
| @item @var{TIME} @tab (Optional) The type shall be @code{CHARACTER(10)} or larger. |
| @item @var{ZONE} @tab (Optional) The type shall be @code{CHARACTER(5)} or larger. |
| @item @var{VALUES}@tab (Optional) The type shall be @code{INTEGER(8)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| None |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_time_and_date |
| character(8) :: date |
| character(10) :: time |
| character(5) :: zone |
| integer,dimension(8) :: values |
| ! using keyword arguments |
| call date_and_time(date,time,zone,values) |
| call date_and_time(DATE=date,ZONE=zone) |
| call date_and_time(TIME=time) |
| call date_and_time(VALUES=values) |
| print '(a,2x,a,2x,a)', date, time, zone |
| print '(8i5))', values |
| end program test_time_and_date |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{CPU_TIME}, @ref{SYSTEM_CLOCK} |
| @end table |
| |
| |
| |
| @node DBLE |
| @section @code{DBLE} --- Double conversion function |
| @fnindex DBLE |
| @cindex conversion, to real |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DBLE(X)} Converts @var{X} to double precision real type. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DBLE(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{INTEGER(*)}, @code{REAL(*)}, |
| or @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type double precision real. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dble |
| real :: x = 2.18 |
| integer :: i = 5 |
| complex :: z = (2.3,1.14) |
| print *, dble(x), dble(i), dble(z) |
| end program test_dble |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{DFLOAT}, @ref{FLOAT}, @ref{REAL} |
| @end table |
| |
| |
| |
| @node DCMPLX |
| @section @code{DCMPLX} --- Double complex conversion function |
| @fnindex DCMPLX |
| @cindex complex numbers, conversion to |
| @cindex conversion, to complex |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DCMPLX(X [,Y])} returns a double complex number where @var{X} is |
| converted to the real component. If @var{Y} is present it is converted to the |
| imaginary component. If @var{Y} is not present then the imaginary component is |
| set to 0.0. If @var{X} is complex then @var{Y} must not be present. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DCMPLX(X [, Y])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type may be @code{INTEGER(*)}, @code{REAL(*)}, |
| or @code{COMPLEX(*)}. |
| @item @var{Y} @tab (Optional if @var{X} is not @code{COMPLEX(*)}.) May be |
| @code{INTEGER(*)} or @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{COMPLEX(8)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dcmplx |
| integer :: i = 42 |
| real :: x = 3.14 |
| complex :: z |
| z = cmplx(i, x) |
| print *, dcmplx(i) |
| print *, dcmplx(x) |
| print *, dcmplx(z) |
| print *, dcmplx(x,i) |
| end program test_dcmplx |
| @end smallexample |
| @end table |
| |
| |
| |
| @node DFLOAT |
| @section @code{DFLOAT} --- Double conversion function |
| @fnindex DFLOAT |
| @cindex conversion, to real |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DFLOAT(X)} Converts @var{X} to double precision real type. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DFLOAT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type double precision real. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dfloat |
| integer :: i = 5 |
| print *, dfloat(i) |
| end program test_dfloat |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{DBLE}, @ref{FLOAT}, @ref{REAL} |
| @end table |
| |
| |
| |
| @node DIGITS |
| @section @code{DIGITS} --- Significant digits function |
| @fnindex DIGITS |
| @cindex model representation, significant digits |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DIGITS(X)} returns the number of significant digits of the internal model |
| representation of @var{X}. For example, on a system using a 32-bit |
| floating point representation, a default real number would likely return 24. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DIGITS(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type may be @code{INTEGER(*)} or @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_digits |
| integer :: i = 12345 |
| real :: x = 3.143 |
| real(8) :: y = 2.33 |
| print *, digits(i) |
| print *, digits(x) |
| print *, digits(y) |
| end program test_digits |
| @end smallexample |
| @end table |
| |
| |
| |
| @node DIM |
| @section @code{DIM} --- Positive difference |
| @fnindex DIM |
| @fnindex IDIM |
| @fnindex DDIM |
| @cindex positive difference |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DIM(X,Y)} returns the difference @code{X-Y} if the result is positive; |
| otherwise returns zero. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DIM(X, Y)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{INTEGER(*)} or @code{REAL(*)} |
| @item @var{Y} @tab The type shall be the same type and kind as @var{X}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} or @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dim |
| integer :: i |
| real(8) :: x |
| i = dim(4, 15) |
| x = dim(4.345_8, 2.111_8) |
| print *, i |
| print *, x |
| end program test_dim |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{IDIM(X,Y)} @tab @code{INTEGER(4) X,Y} @tab @code{INTEGER(4)} @tab F77 and later |
| @item @code{DDIM(X,Y)} @tab @code{REAL(8) X,Y} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node DOT_PRODUCT |
| @section @code{DOT_PRODUCT} --- Dot product function |
| @fnindex DOT_PRODUCT |
| @cindex dot product |
| @cindex vector product |
| @cindex product, vector |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DOT_PRODUCT(X,Y)} computes the dot product multiplication of two vectors |
| @var{X} and @var{Y}. The two vectors may be either numeric or logical |
| and must be arrays of rank one and of equal size. If the vectors are |
| @code{INTEGER(*)} or @code{REAL(*)}, the result is @code{SUM(X*Y)}. If the |
| vectors are @code{COMPLEX(*)}, the result is @code{SUM(CONJG(X)*Y)}. If the |
| vectors are @code{LOGICAL}, the result is @code{ANY(X.AND.Y)}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DOT_PRODUCT(X, Y)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be numeric or @code{LOGICAL}, rank 1. |
| @item @var{Y} @tab The type shall be numeric or @code{LOGICAL}, rank 1. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If the arguments are numeric, the return value is a scaler of numeric type, |
| @code{INTEGER(*)}, @code{REAL(*)}, or @code{COMPLEX(*)}. If the arguments are |
| @code{LOGICAL}, the return value is @code{.TRUE.} or @code{.FALSE.}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dot_prod |
| integer, dimension(3) :: a, b |
| a = (/ 1, 2, 3 /) |
| b = (/ 4, 5, 6 /) |
| print '(3i3)', a |
| print * |
| print '(3i3)', b |
| print * |
| print *, dot_product(a,b) |
| end program test_dot_prod |
| @end smallexample |
| @end table |
| |
| |
| |
| @node DPROD |
| @section @code{DPROD} --- Double product function |
| @fnindex DPROD |
| @cindex product, double-precision |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DPROD(X,Y)} returns the product @code{X*Y}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DPROD(X, Y)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL}. |
| @item @var{Y} @tab The type shall be @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(8)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dprod |
| real :: x = 5.2 |
| real :: y = 2.3 |
| real(8) :: d |
| d = dprod(x,y) |
| print *, d |
| end program test_dprod |
| @end smallexample |
| @end table |
| |
| |
| |
| @node DREAL |
| @section @code{DREAL} --- Double real part function |
| @fnindex DREAL |
| @cindex complex numbers, real part |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DREAL(Z)} returns the real part of complex variable @var{Z}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = DREAL(Z)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{Z} @tab The type shall be @code{COMPLEX(8)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(8)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dreal |
| complex(8) :: z = (1.3_8,7.2_8) |
| print *, dreal(z) |
| end program test_dreal |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{AIMAG} |
| |
| @end table |
| |
| |
| |
| @node DTIME |
| @section @code{DTIME} --- Execution time subroutine (or function) |
| @fnindex DTIME |
| @cindex time, elapsed |
| @cindex elapsed time |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{DTIME(TARRAY, RESULT)} initially returns the number of seconds of runtime |
| since the start of the process's execution in @var{RESULT}. @var{TARRAY} |
| returns the user and system components of this time in @code{TARRAY(1)} and |
| @code{TARRAY(2)} respectively. @var{RESULT} is equal to @code{TARRAY(1) + |
| TARRAY(2)}. |
| |
| Subsequent invocations of @code{DTIME} return values accumulated since the |
| previous invocation. |
| |
| On some systems, the underlying timings are represented using types with |
| sufficiently small limits that overflows (wrap around) are possible, such as |
| 32-bit types. Therefore, the values returned by this intrinsic might be, or |
| become, negative, or numerically less than previous values, during a single |
| run of the compiled program. |
| |
| If @code{DTIME} is invoked as a function, it can not be invoked as a |
| subroutine, and vice versa. |
| |
| @var{TARRAY} and @var{RESULT} are @code{INTENT(OUT)} and provide the following: |
| |
| @multitable @columnfractions .15 .30 .40 |
| @item @tab @code{TARRAY(1)}: @tab User time in seconds. |
| @item @tab @code{TARRAY(2)}: @tab System time in seconds. |
| @item @tab @code{RESULT}: @tab Run time since start in seconds. |
| @end multitable |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL DTIME(TARRAY, RESULT)}. |
| @item @code{RESULT = DTIME(TARRAY)}, (not recommended). |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TARRAY}@tab The type shall be @code{REAL, DIMENSION(2)}. |
| @item @var{RESULT}@tab The type shall be @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Elapsed time in seconds since the start of program execution. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_dtime |
| integer(8) :: i, j |
| real, dimension(2) :: tarray |
| real :: result |
| call dtime(tarray, result) |
| print *, result |
| print *, tarray(1) |
| print *, tarray(2) |
| do i=1,100000000 ! Just a delay |
| j = i * i - i |
| end do |
| call dtime(tarray, result) |
| print *, result |
| print *, tarray(1) |
| print *, tarray(2) |
| end program test_dtime |
| @end smallexample |
| @end table |
| |
| |
| |
| @node EOSHIFT |
| @section @code{EOSHIFT} --- End-off shift elements of an array |
| @fnindex EOSHIFT |
| @cindex array, shift |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{EOSHIFT(ARRAY, SHIFT[,BOUNDARY, DIM])} performs an end-off shift on |
| elements of @var{ARRAY} along the dimension of @var{DIM}. If @var{DIM} is |
| omitted it is taken to be @code{1}. @var{DIM} is a scaler of type |
| @code{INTEGER} in the range of @math{1 /leq DIM /leq n)} where @math{n} is the |
| rank of @var{ARRAY}. If the rank of @var{ARRAY} is one, then all elements of |
| @var{ARRAY} are shifted by @var{SHIFT} places. If rank is greater than one, |
| then all complete rank one sections of @var{ARRAY} along the given dimension are |
| shifted. Elements shifted out one end of each rank one section are dropped. If |
| @var{BOUNDARY} is present then the corresponding value of from @var{BOUNDARY} |
| is copied back in the other end. If @var{BOUNDARY} is not present then the |
| following are copied in depending on the type of @var{ARRAY}. |
| |
| @multitable @columnfractions .15 .80 |
| @item @emph{Array Type} @tab @emph{Boundary Value} |
| @item Numeric @tab 0 of the type and kind of @var{ARRAY}. |
| @item Logical @tab @code{.FALSE.}. |
| @item Character(@var{len}) @tab @var{len} blanks. |
| @end multitable |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = EOSHIFT(A, SHIFT [, BOUNDARY, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab May be any type, not scaler. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER}. |
| @item @var{BOUNDARY} @tab Same type as @var{ARRAY}. |
| @item @var{DIM} @tab The type shall be @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns an array of same type and rank as the @var{ARRAY} argument. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_eoshift |
| integer, dimension(3,3) :: a |
| a = reshape( (/ 1, 2, 3, 4, 5, 6, 7, 8, 9 /), (/ 3, 3 /)) |
| print '(3i3)', a(1,:) |
| print '(3i3)', a(2,:) |
| print '(3i3)', a(3,:) |
| a = EOSHIFT(a, SHIFT=(/1, 2, 1/), BOUNDARY=-5, DIM=2) |
| print * |
| print '(3i3)', a(1,:) |
| print '(3i3)', a(2,:) |
| print '(3i3)', a(3,:) |
| end program test_eoshift |
| @end smallexample |
| @end table |
| |
| |
| |
| @node EPSILON |
| @section @code{EPSILON} --- Epsilon function |
| @fnindex EPSILON |
| @cindex model representation, epsilon |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{EPSILON(X)} returns a nearly negligible number relative to @code{1}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = EPSILON(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of same type as the argument. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_epsilon |
| real :: x = 3.143 |
| real(8) :: y = 2.33 |
| print *, EPSILON(x) |
| print *, EPSILON(y) |
| end program test_epsilon |
| @end smallexample |
| @end table |
| |
| |
| |
| @node ERF |
| @section @code{ERF} --- Error function |
| @fnindex ERF |
| @cindex error function |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ERF(X)} computes the error function of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU Extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ERF(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)} and it is positive |
| (@math{ - 1 \leq erf (x) \leq 1 }. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_erf |
| real(8) :: x = 0.17_8 |
| x = erf(x) |
| end program test_erf |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DERF(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node ERFC |
| @section @code{ERFC} --- Error function |
| @fnindex ERFC |
| @cindex error function, complementary |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ERFC(X)} computes the complementary error function of @var{X}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ERFC(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}, and it shall be scalar. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{REAL(*)} and it is positive |
| (@math{ 0 \leq erfc (x) \leq 2 }. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_erfc |
| real(8) :: x = 0.17_8 |
| x = erfc(x) |
| end program test_erfc |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DERFC(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node ETIME |
| @section @code{ETIME} --- Execution time subroutine (or function) |
| @fnindex ETIME |
| @cindex time, elapsed |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ETIME(TARRAY, RESULT)} returns the number of seconds of runtime |
| since the start of the process's execution in @var{RESULT}. @var{TARRAY} |
| returns the user and system components of this time in @code{TARRAY(1)} and |
| @code{TARRAY(2)} respectively. @var{RESULT} is equal to @code{TARRAY(1) + TARRAY(2)}. |
| |
| On some systems, the underlying timings are represented using types with |
| sufficiently small limits that overflows (wrap around) are possible, such as |
| 32-bit types. Therefore, the values returned by this intrinsic might be, or |
| become, negative, or numerically less than previous values, during a single |
| run of the compiled program. |
| |
| If @code{ETIME} is invoked as a function, it can not be invoked as a |
| subroutine, and vice versa. |
| |
| @var{TARRAY} and @var{RESULT} are @code{INTENT(OUT)} and provide the following: |
| |
| @multitable @columnfractions .15 .30 .60 |
| @item @tab @code{TARRAY(1)}: @tab User time in seconds. |
| @item @tab @code{TARRAY(2)}: @tab System time in seconds. |
| @item @tab @code{RESULT}: @tab Run time since start in seconds. |
| @end multitable |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL ETIME(TARRAY, RESULT)}. |
| @item @code{RESULT = ETIME(TARRAY)}, (not recommended). |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TARRAY}@tab The type shall be @code{REAL, DIMENSION(2)}. |
| @item @var{RESULT}@tab The type shall be @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Elapsed time in seconds since the start of program execution. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_etime |
| integer(8) :: i, j |
| real, dimension(2) :: tarray |
| real :: result |
| call ETIME(tarray, result) |
| print *, result |
| print *, tarray(1) |
| print *, tarray(2) |
| do i=1,100000000 ! Just a delay |
| j = i * i - i |
| end do |
| call ETIME(tarray, result) |
| print *, result |
| print *, tarray(1) |
| print *, tarray(2) |
| end program test_etime |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{CPU_TIME} |
| |
| @end table |
| |
| |
| |
| @node EXIT |
| @section @code{EXIT} --- Exit the program with status. |
| @fnindex EXIT |
| @cindex program termination |
| @cindex terminate program |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{EXIT} causes immediate termination of the program with status. If status |
| is omitted it returns the canonical @emph{success} for the system. All Fortran |
| I/O units are closed. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL EXIT([STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STATUS} @tab Shall be an @code{INTEGER} of the default kind. |
| @end multitable |
| |
| @item @emph{Return value}: |
| @code{STATUS} is passed to the parent process on exit. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_exit |
| integer :: STATUS = 0 |
| print *, 'This program is going to exit.' |
| call EXIT(STATUS) |
| end program test_exit |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ABORT}, @ref{KILL} |
| @end table |
| |
| |
| |
| @node EXP |
| @section @code{EXP} --- Exponential function |
| @fnindex EXP |
| @fnindex DEXP |
| @fnindex CEXP |
| @fnindex ZEXP |
| @fnindex CDEXP |
| @cindex exponential function |
| @cindex logarithmic function, inverse |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{EXP(X)} computes the base @math{e} exponential of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later, has overloads that are GNU extensions |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = EXP(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} or |
| @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value has same type and kind as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_exp |
| real :: x = 1.0 |
| x = exp(x) |
| end program test_exp |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DEXP(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @item @code{CEXP(X)} @tab @code{COMPLEX(4) X} @tab @code{COMPLEX(4)} @tab F77 and later |
| @item @code{ZEXP(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @item @code{CDEXP(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node EXPONENT |
| @section @code{EXPONENT} --- Exponent function |
| @fnindex EXPONENT |
| @cindex real number, exponent |
| @cindex floating point, exponent |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{EXPONENT(X)} returns the value of the exponent part of @var{X}. If @var{X} |
| is zero the value returned is zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = EXPONENT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type default @code{INTEGER}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_exponent |
| real :: x = 1.0 |
| integer :: i |
| i = exponent(x) |
| print *, i |
| print *, exponent(0.0) |
| end program test_exponent |
| @end smallexample |
| @end table |
| |
| |
| |
| @node FDATE |
| @section @code{FDATE} --- Get the current time as a string |
| @fnindex FDATE |
| @cindex time, current |
| @cindex current time |
| @cindex date, current |
| @cindex current date |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FDATE(DATE)} returns the current date (using the same format as |
| @code{CTIME}) in @var{DATE}. It is equivalent to @code{CALL CTIME(DATE, |
| TIME())}. |
| |
| If @code{FDATE} is invoked as a function, it can not be invoked as a |
| subroutine, and vice versa. |
| |
| @var{DATE} is an @code{INTENT(OUT)} @code{CHARACTER} variable. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL FDATE(DATE)}. |
| @item @code{DATE = FDATE()}, (not recommended). |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{DATE}@tab The type shall be of type @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The current date as a string. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_fdate |
| integer(8) :: i, j |
| character(len=30) :: date |
| call fdate(date) |
| print *, 'Program started on ', date |
| do i = 1, 100000000 ! Just a delay |
| j = i * i - i |
| end do |
| call fdate(date) |
| print *, 'Program ended on ', date |
| end program test_fdate |
| @end smallexample |
| @end table |
| |
| |
| |
| @node FLOAT |
| @section @code{FLOAT} --- Convert integer to default real |
| @fnindex FLOAT |
| @cindex conversion, to real |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FLOAT(I)} converts the integer @var{I} to a default real value. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = FLOAT(I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type default @code{REAL}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_float |
| integer :: i = 1 |
| if (float(i) /= 1.) call abort |
| end program test_float |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{DBLE}, @ref{DFLOAT}, @ref{REAL} |
| @end table |
| |
| |
| |
| @node FGET |
| @section @code{FGET} --- Read a single character in stream mode from stdin |
| @fnindex FGET |
| @cindex read character, stream mode |
| @cindex stream mode, read character |
| @cindex file operation, read character |
| |
| @table @asis |
| @item @emph{Description}: |
| Read a single character in stream mode from stdin by bypassing normal |
| formatted output. Stream I/O should not be mixed with normal record-oriented |
| (formatted or unformatted) I/O on the same unit; the results are unpredictable. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| @command{g77}. GNU Fortran provides the Fortran 2003 Stream facility. |
| Programmers should consider the use of new stream IO feature in new code |
| for future portability. See also @ref{Fortran 2003 status}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FGET(C [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{C} @tab The type shall be @code{CHARACTER}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER}. |
| Returns 0 on success, -1 on end-of-file, and a |
| system specific positive error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_fget |
| INTEGER, PARAMETER :: strlen = 100 |
| INTEGER :: status, i = 1 |
| CHARACTER(len=strlen) :: str = "" |
| |
| WRITE (*,*) 'Enter text:' |
| DO |
| CALL fget(str(i:i), status) |
| if (status /= 0 .OR. i > strlen) exit |
| i = i + 1 |
| END DO |
| WRITE (*,*) TRIM(str) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FGETC}, @ref{FPUT}, @ref{FPUTC} |
| @end table |
| |
| |
| |
| @node FGETC |
| @section @code{FGETC} --- Read a single character in stream mode |
| @fnindex FGETC |
| @cindex read character, stream mode |
| @cindex stream mode, read character |
| @cindex file operation, read character |
| |
| @table @asis |
| @item @emph{Description}: |
| Read a single character in stream mode by bypassing normal formatted output. |
| Stream I/O should not be mixed with normal record-oriented (formatted or |
| unformatted) I/O on the same unit; the results are unpredictable. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| @command{g77}. GNU Fortran provides the Fortran 2003 Stream facility. |
| Programmers should consider the use of new stream IO feature in new code |
| for future portability. See also @ref{Fortran 2003 status}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FGETC(UNIT, C [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab The type shall be @code{INTEGER}. |
| @item @var{C} @tab The type shall be @code{CHARACTER}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER}. Returns 0 on success, |
| -1 on end-of-file and a system specific positive error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_fgetc |
| INTEGER :: fd = 42, status |
| CHARACTER :: c |
| |
| OPEN(UNIT=fd, FILE="/etc/passwd", ACTION="READ", STATUS = "OLD") |
| DO |
| CALL fgetc(fd, c, status) |
| IF (status /= 0) EXIT |
| call fput(c) |
| END DO |
| CLOSE(UNIT=fd) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FGET}, @ref{FPUT}, @ref{FPUTC} |
| @end table |
| |
| |
| |
| @node FLOOR |
| @section @code{FLOOR} --- Integer floor function |
| @fnindex FLOOR |
| @cindex floor |
| @cindex rounding, floor |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FLOOR(X)} returns the greatest integer less than or equal to @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = FLOOR(X [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(KIND)} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_floor |
| real :: x = 63.29 |
| real :: y = -63.59 |
| print *, floor(x) ! returns 63 |
| print *, floor(y) ! returns -64 |
| end program test_floor |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{CEILING}, @ref{NINT} |
| |
| @end table |
| |
| |
| |
| @node FLUSH |
| @section @code{FLUSH} --- Flush I/O unit(s) |
| @fnindex FLUSH |
| @cindex file operation, flush |
| |
| @table @asis |
| @item @emph{Description}: |
| Flushes Fortran unit(s) currently open for output. Without the optional |
| argument, all units are flushed, otherwise just the unit specified. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FLUSH(UNIT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab (Optional) The type shall be @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Note}: |
| Beginning with the Fortran 2003 standard, there is a @code{FLUSH} |
| statement that should be preferred over the @code{FLUSH} intrinsic. |
| |
| @end table |
| |
| |
| |
| @node FNUM |
| @section @code{FNUM} --- File number function |
| @fnindex FNUM |
| @cindex file operation, file number |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FNUM(UNIT)} returns the POSIX file descriptor number corresponding to the |
| open Fortran I/O unit @code{UNIT}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = FNUM(UNIT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab The type shall be @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_fnum |
| integer :: i |
| open (unit=10, status = "scratch") |
| i = fnum(10) |
| print *, i |
| close (10) |
| end program test_fnum |
| @end smallexample |
| @end table |
| |
| |
| |
| @node FPUT |
| @section @code{FPUT} --- Write a single character in stream mode to stdout |
| @fnindex FPUT |
| @cindex write character, stream mode |
| @cindex stream mode, write character |
| @cindex file operation, write character |
| |
| @table @asis |
| @item @emph{Description}: |
| Write a single character in stream mode to stdout by bypassing normal |
| formatted output. Stream I/O should not be mixed with normal record-oriented |
| (formatted or unformatted) I/O on the same unit; the results are unpredictable. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| @command{g77}. GNU Fortran provides the Fortran 2003 Stream facility. |
| Programmers should consider the use of new stream IO feature in new code |
| for future portability. See also @ref{Fortran 2003 status}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FPUT(C [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{C} @tab The type shall be @code{CHARACTER}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER}. Returns 0 on success, |
| -1 on end-of-file and a system specific positive error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_fput |
| CHARACTER(len=10) :: str = "gfortran" |
| INTEGER :: i |
| DO i = 1, len_trim(str) |
| CALL fput(str(i:i)) |
| END DO |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FPUTC}, @ref{FGET}, @ref{FGETC} |
| @end table |
| |
| |
| |
| @node FPUTC |
| @section @code{FPUTC} --- Write a single character in stream mode |
| @fnindex FPUTC |
| @cindex write character, stream mode |
| @cindex stream mode, write character |
| @cindex file operation, write character |
| |
| @table @asis |
| @item @emph{Description}: |
| Write a single character in stream mode by bypassing normal formatted |
| output. Stream I/O should not be mixed with normal record-oriented |
| (formatted or unformatted) I/O on the same unit; the results are unpredictable. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| @command{g77}. GNU Fortran provides the Fortran 2003 Stream facility. |
| Programmers should consider the use of new stream IO feature in new code |
| for future portability. See also @ref{Fortran 2003 status}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FPUTC(UNIT, C [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab The type shall be @code{INTEGER}. |
| @item @var{C} @tab The type shall be @code{CHARACTER}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER}. Returns 0 on success, |
| -1 on end-of-file and a system specific positive error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_fputc |
| CHARACTER(len=10) :: str = "gfortran" |
| INTEGER :: fd = 42, i |
| |
| OPEN(UNIT = fd, FILE = "out", ACTION = "WRITE", STATUS="NEW") |
| DO i = 1, len_trim(str) |
| CALL fputc(fd, str(i:i)) |
| END DO |
| CLOSE(fd) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FPUT}, @ref{FGET}, @ref{FGETC} |
| @end table |
| |
| |
| |
| @node FRACTION |
| @section @code{FRACTION} --- Fractional part of the model representation |
| @fnindex FRACTION |
| @cindex real number, fraction |
| @cindex floating point, fraction |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FRACTION(X)} returns the fractional part of the model |
| representation of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{Y = FRACTION(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be a @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as the argument. |
| The fractional part of the model representation of @code{X} is returned; |
| it is @code{X * RADIX(X)**(-EXPONENT(X))}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_fraction |
| real :: x |
| x = 178.1387e-4 |
| print *, fraction(x), x * radix(x)**(-exponent(x)) |
| end program test_fraction |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node FREE |
| @section @code{FREE} --- Frees memory |
| @fnindex FREE |
| @cindex pointer, cray |
| |
| @table @asis |
| @item @emph{Description}: |
| Frees memory previously allocated by @code{MALLOC()}. The @code{FREE} |
| intrinsic is an extension intended to be used with Cray pointers, and is |
| provided in GNU Fortran to allow user to compile legacy code. For |
| new code using Fortran 95 pointers, the memory de-allocation intrinsic is |
| @code{DEALLOCATE}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FREE(PTR)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PTR} @tab The type shall be @code{INTEGER}. It represents the |
| location of the memory that should be de-allocated. |
| @end multitable |
| |
| @item @emph{Return value}: |
| None |
| |
| @item @emph{Example}: |
| See @code{MALLOC} for an example. |
| |
| @item @emph{See also}: |
| @ref{MALLOC} |
| @end table |
| |
| |
| |
| @node FSEEK |
| @section @code{FSEEK} --- Low level file positioning subroutine |
| @fnindex FSEEK |
| @cindex file operation, seek |
| @cindex file operation, position |
| |
| Not yet implemented in GNU Fortran. |
| |
| @table @asis |
| @item @emph{Description}: |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @item @emph{Arguments}: |
| @item @emph{Return value}: |
| @item @emph{Example}: |
| @item @emph{Specific names}: |
| @item @emph{See also}: |
| @uref{http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19292, g77 features lacking in gfortran} |
| |
| @end table |
| |
| |
| |
| @node FSTAT |
| @section @code{FSTAT} --- Get file status |
| @fnindex FSTAT |
| @cindex file system, file status |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{FSTAT} is identical to @ref{STAT}, except that information about an |
| already opened file is obtained. |
| |
| The elements in @code{BUFF} are the same as described by @ref{STAT}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL FSTAT(UNIT, BUFF [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab An open I/O unit number of type @code{INTEGER}. |
| @item @var{BUFF} @tab The type shall be @code{INTEGER(4), DIMENSION(13)}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER(4)}. Returns 0 |
| on success and a system specific error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| See @ref{STAT} for an example. |
| |
| @item @emph{See also}: |
| To stat a link: @ref{LSTAT}, to stat a file: @ref{STAT} |
| @end table |
| |
| |
| |
| @node FTELL |
| @section @code{FTELL} --- Current stream position |
| @fnindex FTELL |
| @cindex file operation, position |
| |
| @table @asis |
| @item @emph{Description}: |
| Retrieves the current position within an open file. |
| |
| This intrinsic is provided in both subroutine and function forms; however, |
| only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL FTELL(UNIT, OFFSET)} |
| @item @code{OFFSET = FTELL(UNIT)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{OFFSET} @tab Shall of type @code{INTEGER}. |
| @item @var{UNIT} @tab Shall of type @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| In either syntax, @var{OFFSET} is set to the current offset of unit |
| number @var{UNIT}, or to @math{-1} if the unit is not currently open. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_ftell |
| INTEGER :: i |
| OPEN(10, FILE="temp.dat") |
| CALL ftell(10,i) |
| WRITE(*,*) i |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FSEEK} |
| @end table |
| |
| |
| |
| @node GERROR |
| @section @code{GERROR} --- Get last system error message |
| @fnindex GERROR |
| @cindex system, error handling |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the system error message corresponding to the last system error. |
| This resembles the functionality of @code{strerror(3)} in C. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GERROR(RESULT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{RESULT} @tab Shall of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_gerror |
| CHARACTER(len=100) :: msg |
| CALL gerror(msg) |
| WRITE(*,*) msg |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{IERRNO}, @ref{PERROR} |
| @end table |
| |
| |
| |
| @node GETARG |
| @section @code{GETARG} --- Get command line arguments |
| @fnindex GETARG |
| @cindex command-line arguments |
| @cindex arguments, to program |
| |
| @table @asis |
| @item @emph{Description}: |
| Retrieve the @var{N}th argument that was passed on the |
| command line when the containing program was invoked. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. In new code, programmers should consider the use of |
| the @ref{GET_COMMAND_ARGUMENT} intrinsic defined by the Fortran 2003 |
| standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GETARG(N, ARG)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{N} @tab Shall be of type @code{INTEGER(4)}, @math{@var{N} \geq 0} |
| @item @var{ARG} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| After @code{GETARG} returns, the @var{ARG} argument holds the @var{N}th |
| command line argument. If @var{ARG} can not hold the argument, it is |
| truncated to fit the length of @var{ARG}. If there are less than @var{N} |
| arguments specified at the command line, @var{ARG} will be filled with blanks. |
| If @math{@var{N} = 0}, @var{ARG} is set to the name of the program (on systems |
| that support this feature). |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_getarg |
| INTEGER :: i |
| CHARACTER(len=32) :: arg |
| |
| DO i = 1, iargc() |
| CALL getarg(i, arg) |
| WRITE (*,*) arg |
| END DO |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| GNU Fortran 77 compatibility function: @ref{IARGC} |
| |
| F2003 functions and subroutines: @ref{GET_COMMAND}, @ref{GET_COMMAND_ARGUMENT}, |
| @ref{COMMAND_ARGUMENT_COUNT} |
| @end table |
| |
| |
| |
| @node GET_COMMAND |
| @section @code{GET_COMMAND} --- Get the entire command line |
| @fnindex GET_COMMAND |
| @cindex command-line arguments |
| @cindex arguments, to program |
| |
| @table @asis |
| @item @emph{Description}: |
| Retrieve the entire command line that was used to invoke the program. |
| |
| @item @emph{Standard}: |
| F2003 |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GET_COMMAND(CMD)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{CMD} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Stores the entire command line that was used to invoke the program in @var{ARG}. |
| If @var{ARG} is not large enough, the command will be truncated. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_get_command |
| CHARACTER(len=255) :: cmd |
| CALL get_command(cmd) |
| WRITE (*,*) TRIM(cmd) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GET_COMMAND_ARGUMENT}, @ref{COMMAND_ARGUMENT_COUNT} |
| @end table |
| |
| |
| |
| @node GET_COMMAND_ARGUMENT |
| @section @code{GET_COMMAND_ARGUMENT} --- Get command line arguments |
| @fnindex GET_COMMAND_ARGUMENT |
| @cindex command-line arguments |
| @cindex arguments, to program |
| |
| @table @asis |
| @item @emph{Description}: |
| Retrieve the @var{N}th argument that was passed on the |
| command line when the containing program was invoked. |
| |
| @item @emph{Standard}: |
| F2003 |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GET_COMMAND_ARGUMENT(N, ARG)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{N} @tab Shall be of type @code{INTEGER(4)}, @math{@var{N} \geq 0} |
| @item @var{ARG} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| After @code{GET_COMMAND_ARGUMENT} returns, the @var{ARG} argument holds the |
| @var{N}th command line argument. If @var{ARG} can not hold the argument, it is |
| truncated to fit the length of @var{ARG}. If there are less than @var{N} |
| arguments specified at the command line, @var{ARG} will be filled with blanks. |
| If @math{@var{N} = 0}, @var{ARG} is set to the name of the program (on systems |
| that support this feature). |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_get_command_argument |
| INTEGER :: i |
| CHARACTER(len=32) :: arg |
| |
| i = 0 |
| DO |
| CALL get_command_argument(i, arg) |
| IF (LEN_TRIM(arg) == 0) EXIT |
| |
| WRITE (*,*) TRIM(arg) |
| i = i+1 |
| END DO |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GET_COMMAND}, @ref{COMMAND_ARGUMENT_COUNT} |
| @end table |
| |
| |
| |
| @node GETCWD |
| @section @code{GETCWD} --- Get current working directory |
| @fnindex GETCWD |
| @cindex system, working directory |
| |
| @table @asis |
| @item @emph{Description}: |
| Get current working directory. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine. |
| |
| @item @emph{Syntax}: |
| @code{CALL GETCWD(CWD [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{CWD} @tab The type shall be @code{CHARACTER(*)}. |
| @item @var{STATUS} @tab (Optional) status flag. Returns 0 on success, |
| a system specific and non-zero error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_getcwd |
| CHARACTER(len=255) :: cwd |
| CALL getcwd(cwd) |
| WRITE(*,*) TRIM(cwd) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{CHDIR} |
| @end table |
| |
| |
| |
| @node GETENV |
| @section @code{GETENV} --- Get an environmental variable |
| @fnindex GETENV |
| @cindex environment variable |
| |
| @table @asis |
| @item @emph{Description}: |
| Get the @var{VALUE} of the environmental variable @var{ENVVAR}. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. In new code, programmers should consider the use of |
| the @ref{GET_ENVIRONMENT_VARIABLE} intrinsic defined by the Fortran |
| 2003 standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GETENV(ENVVAR, VALUE)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ENVVAR} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{VALUE} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Stores the value of @var{ENVVAR} in @var{VALUE}. If @var{VALUE} is |
| not large enough to hold the data, it is truncated. If @var{ENVVAR} |
| is not set, @var{VALUE} will be filled with blanks. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_getenv |
| CHARACTER(len=255) :: homedir |
| CALL getenv("HOME", homedir) |
| WRITE (*,*) TRIM(homedir) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GET_ENVIRONMENT_VARIABLE} |
| @end table |
| |
| |
| |
| @node GET_ENVIRONMENT_VARIABLE |
| @section @code{GET_ENVIRONMENT_VARIABLE} --- Get an environmental variable |
| @fnindex GET_ENVIRONMENT_VARIABLE |
| @cindex environment variable |
| |
| @table @asis |
| @item @emph{Description}: |
| Get the @var{VALUE} of the environmental variable @var{ENVVAR}. |
| |
| @item @emph{Standard}: |
| F2003 |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GET_ENVIRONMENT_VARIABLE(ENVVAR, VALUE)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ENVVAR} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{VALUE} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Stores the value of @var{ENVVAR} in @var{VALUE}. If @var{VALUE} is |
| not large enough to hold the data, it is truncated. If @var{ENVVAR} |
| is not set, @var{VALUE} will be filled with blanks. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_getenv |
| CHARACTER(len=255) :: homedir |
| CALL get_environment_variable("HOME", homedir) |
| WRITE (*,*) TRIM(homedir) |
| END PROGRAM |
| @end smallexample |
| @end table |
| |
| |
| |
| @node GETGID |
| @section @code{GETGID} --- Group ID function |
| @fnindex GETGID |
| @cindex system, group id |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the numerical group ID of the current process. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = GETGID()} |
| |
| @item @emph{Return value}: |
| The return value of @code{GETGID} is an @code{INTEGER} of the default |
| kind. |
| |
| |
| @item @emph{Example}: |
| See @code{GETPID} for an example. |
| |
| @item @emph{See also}: |
| @ref{GETPID}, @ref{GETUID} |
| @end table |
| |
| |
| |
| @node GETLOG |
| @section @code{GETLOG} --- Get login name |
| @fnindex GETLOG |
| @cindex system, login name |
| @cindex login name |
| |
| @table @asis |
| @item @emph{Description}: |
| Gets the username under which the program is running. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GETLOG(LOGIN)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{LOGIN} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Stores the current user name in @var{LOGIN}. (On systems where |
| the @code{getlogin(3)} function is not implemented, this will |
| return a blank string.) |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM TEST_GETLOG |
| CHARACTER(32) :: login |
| CALL GETLOG(login) |
| WRITE(*,*) login |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GETUID} |
| @end table |
| |
| |
| |
| @node GETPID |
| @section @code{GETPID} --- Process ID function |
| @fnindex GETPID |
| @cindex system, process id |
| @cindex process id |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the numerical process identifier of the current process. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = GETPID()} |
| |
| @item @emph{Return value}: |
| The return value of @code{GETPID} is an @code{INTEGER} of the default |
| kind. |
| |
| |
| @item @emph{Example}: |
| @smallexample |
| program info |
| print *, "The current process ID is ", getpid() |
| print *, "Your numerical user ID is ", getuid() |
| print *, "Your numerical group ID is ", getgid() |
| end program info |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{GETGID}, @ref{GETUID} |
| @end table |
| |
| |
| |
| @node GETUID |
| @section @code{GETUID} --- User ID function |
| @fnindex GETUID |
| @cindex system, user id |
| @cindex user id |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the numerical user ID of the current process. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = GETUID()} |
| |
| @item @emph{Return value}: |
| The return value of @code{GETUID} is an @code{INTEGER} of the default |
| kind. |
| |
| |
| @item @emph{Example}: |
| See @code{GETPID} for an example. |
| |
| @item @emph{See also}: |
| @ref{GETPID}, @ref{GETLOG} |
| @end table |
| |
| |
| |
| @node GMTIME |
| @section @code{GMTIME} --- Convert time to GMT info |
| @fnindex GMTIME |
| @cindex time, conversion to GMT info |
| |
| @table @asis |
| @item @emph{Description}: |
| Given a system time value @var{STIME} (as provided by the @code{TIME8()} |
| intrinsic), fills @var{TARRAY} with values extracted from it appropriate |
| to the UTC time zone (Universal Coordinated Time, also known in some |
| countries as GMT, Greenwich Mean Time), using @code{gmtime(3)}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL GMTIME(STIME, TARRAY)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STIME} @tab An @code{INTEGER(*)} scalar expression |
| corresponding to a system time, with |
| @code{INTENT(IN)}. |
| @item @var{TARRAY} @tab A default @code{INTEGER} array with 9 elements, |
| with @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The elements of @var{TARRAY} are assigned as follows: |
| @enumerate |
| @item Seconds after the minute, range 0--59 or 0--61 to allow for leap |
| seconds |
| @item Minutes after the hour, range 0--59 |
| @item Hours past midnight, range 0--23 |
| @item Day of month, range 0--31 |
| @item Number of months since January, range 0--12 |
| @item Years since 1900 |
| @item Number of days since Sunday, range 0--6 |
| @item Days since January 1 |
| @item Daylight savings indicator: positive if daylight savings is in |
| effect, zero if not, and negative if the information is not |
| available. |
| @end enumerate |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{LTIME}, @ref{TIME}, @ref{TIME8} |
| |
| @end table |
| |
| |
| |
| @node HOSTNM |
| @section @code{HOSTNM} --- Get system host name |
| @fnindex HOSTNM |
| @cindex system, host name |
| |
| @table @asis |
| @item @emph{Description}: |
| Retrieves the host name of the system on which the program is running. |
| |
| This intrinsic is provided in both subroutine and function forms; however, |
| only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL HOSTNM(NAME[, STATUS])} |
| @item @code{STATUS = HOSTNM(NAME)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{NAME} @tab Shall of type @code{CHARACTER(*)}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER}. |
| Returns 0 on success, or a system specific error |
| code otherwise. |
| @end multitable |
| |
| @item @emph{Return value}: |
| In either syntax, @var{NAME} is set to the current hostname if it can |
| be obtained, or to a blank string otherwise. |
| |
| @end table |
| |
| |
| |
| @node HUGE |
| @section @code{HUGE} --- Largest number of a kind |
| @fnindex HUGE |
| @cindex limits, largest number |
| @cindex model representation, largest number |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{HUGE(X)} returns the largest number that is not an infinity in |
| the model of the type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = HUGE(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL} or @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as @var{X} |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_huge_tiny |
| print *, huge(0), huge(0.0), huge(0.0d0) |
| print *, tiny(0.0), tiny(0.0d0) |
| end program test_huge_tiny |
| @end smallexample |
| @end table |
| |
| |
| |
| @node IACHAR |
| @section @code{IACHAR} --- Code in @acronym{ASCII} collating sequence |
| @fnindex IACHAR |
| @cindex @acronym{ASCII} collating sequence |
| @cindex collating sequence, @acronym{ASCII} |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IACHAR(C)} returns the code for the @acronym{ASCII} character |
| in the first character position of @code{C}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IACHAR(C)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{C} @tab Shall be a scalar @code{CHARACTER}, with @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_iachar |
| integer i |
| i = iachar(' ') |
| end program test_iachar |
| @end smallexample |
| |
| @item @emph{Note}: |
| See @ref{ICHAR} for a discussion of converting between numerical values |
| and formatted string representations. |
| |
| @item @emph{See also}: |
| @ref{ACHAR}, @ref{CHAR}, @ref{ICHAR} |
| |
| @end table |
| |
| |
| |
| @node IAND |
| @section @code{IAND} --- Bitwise logical and |
| @fnindex IAND |
| @cindex bitwise logical and |
| @cindex logical and, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| Bitwise logical @code{AND}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IAND(I, J)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{J} @tab The type shall be @code{INTEGER(*)}, of the same |
| kind as @var{I}. (As a GNU extension, different kinds are also |
| permitted.) |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is @code{INTEGER(*)}, of the same kind as the |
| arguments. (If the argument kinds differ, it is of the same kind as |
| the larger argument.) |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_iand |
| INTEGER :: a, b |
| DATA a / Z'F' /, b / Z'3' / |
| WRITE (*,*) IAND(a, b) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{IOR}, @ref{IEOR}, @ref{IBITS}, @ref{IBSET}, @ref{IBCLR}, @ref{NOT} |
| |
| @end table |
| |
| |
| |
| @node IARGC |
| @section @code{IARGC} --- Get the number of command line arguments |
| @fnindex IARGC |
| @cindex command-line arguments |
| @cindex command-line arguments, number of |
| @cindex arguments, to program |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IARGC()} returns the number of arguments passed on the |
| command line when the containing program was invoked. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. In new code, programmers should consider the use of |
| the @ref{COMMAND_ARGUMENT_COUNT} intrinsic defined by the Fortran 2003 |
| standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental Function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IARGC()} |
| |
| @item @emph{Arguments}: |
| None. |
| |
| @item @emph{Return value}: |
| The number of command line arguments, type @code{INTEGER(4)}. |
| |
| @item @emph{Example}: |
| See @ref{GETARG} |
| |
| @item @emph{See also}: |
| GNU Fortran 77 compatibility subroutine: @ref{GETARG} |
| |
| F2003 functions and subroutines: @ref{GET_COMMAND}, @ref{GET_COMMAND_ARGUMENT}, |
| @ref{COMMAND_ARGUMENT_COUNT} |
| @end table |
| |
| |
| |
| @node IBCLR |
| @section @code{IBCLR} --- Clear bit |
| @fnindex IBCLR |
| @cindex bits, unset |
| @cindex bits, clear |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IBCLR} returns the value of @var{I} with the bit at position |
| @var{POS} set to zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IBCLR(I, POS)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{POS} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{IBITS}, @ref{IBSET}, @ref{IAND}, @ref{IOR}, @ref{IEOR}, @ref{MVBITS} |
| |
| @end table |
| |
| |
| |
| @node IBITS |
| @section @code{IBITS} --- Bit extraction |
| @fnindex IBITS |
| @cindex bits, get |
| @cindex bits, extract |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IBITS} extracts a field of length @var{LEN} from @var{I}, |
| starting from bit position @var{POS} and extending left for @var{LEN} |
| bits. The result is right-justified and the remaining bits are |
| zeroed. The value of @code{POS+LEN} must be less than or equal to the |
| value @code{BIT_SIZE(I)}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IBITS(I, POS, LEN)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{POS} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{LEN} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{BIT_SIZE}, @ref{IBCLR}, @ref{IBSET}, @ref{IAND}, @ref{IOR}, @ref{IEOR} |
| @end table |
| |
| |
| |
| @node IBSET |
| @section @code{IBSET} --- Set bit |
| @fnindex IBSET |
| @cindex bits, set |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IBSET} returns the value of @var{I} with the bit at position |
| @var{POS} set to one. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IBSET(I, POS)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{POS} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{IBCLR}, @ref{IBITS}, @ref{IAND}, @ref{IOR}, @ref{IEOR}, @ref{MVBITS} |
| |
| @end table |
| |
| |
| |
| @node ICHAR |
| @section @code{ICHAR} --- Character-to-integer conversion function |
| @fnindex ICHAR |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ICHAR(C)} returns the code for the character in the first character |
| position of @code{C} in the system's native character set. |
| The correspondence between characters and their codes is not necessarily |
| the same across different GNU Fortran implementations. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ICHAR(C)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{C} @tab Shall be a scalar @code{CHARACTER}, with @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_ichar |
| integer i |
| i = ichar(' ') |
| end program test_ichar |
| @end smallexample |
| |
| @item @emph{Note}: |
| No intrinsic exists to convert between a numeric value and a formatted |
| character string representation -- for instance, given the |
| @code{CHARACTER} value @code{'154'}, obtaining an @code{INTEGER} or |
| @code{REAL} value with the value 154, or vice versa. Instead, this |
| functionality is provided by internal-file I/O, as in the following |
| example: |
| @smallexample |
| program read_val |
| integer value |
| character(len=10) string, string2 |
| string = '154' |
| |
| ! Convert a string to a numeric value |
| read (string,'(I10)') value |
| print *, value |
| |
| ! Convert a value to a formatted string |
| write (string2,'(I10)') value |
| print *, string2 |
| end program read_val |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ACHAR}, @ref{CHAR}, @ref{IACHAR} |
| |
| @end table |
| |
| |
| |
| @node IDATE |
| @section @code{IDATE} --- Get current local time subroutine (day/month/year) |
| @fnindex IDATE |
| @cindex date, current |
| @cindex current date |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IDATE(TARRAY)} Fills @var{TARRAY} with the numerical values at the |
| current local time. The day (in the range 1-31), month (in the range 1-12), |
| and year appear in elements 1, 2, and 3 of @var{TARRAY}, respectively. |
| The year has four significant digits. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL IDATE(TARRAY)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TARRAY} @tab The type shall be @code{INTEGER, DIMENSION(3)} and |
| the kind shall be the default integer kind. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Does not return. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_idate |
| integer, dimension(3) :: tarray |
| call idate(tarray) |
| print *, tarray(1) |
| print *, tarray(2) |
| print *, tarray(3) |
| end program test_idate |
| @end smallexample |
| @end table |
| |
| |
| |
| @node IEOR |
| @section @code{IEOR} --- Bitwise logical exclusive or |
| @fnindex IEOR |
| @cindex bitwise logical exclusive or |
| @cindex logical exclusive or, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IEOR} returns the bitwise boolean exclusive-OR of @var{I} and |
| @var{J}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IEOR(I, J)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{J} @tab The type shall be @code{INTEGER(*)}, of the same |
| kind as @var{I}. (As a GNU extension, different kinds are also |
| permitted.) |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is @code{INTEGER(*)}, of the same kind as the |
| arguments. (If the argument kinds differ, it is of the same kind as |
| the larger argument.) |
| |
| @item @emph{See also}: |
| @ref{IOR}, @ref{IAND}, @ref{IBITS}, @ref{IBSET}, @ref{IBCLR}, @ref{NOT} |
| @end table |
| |
| |
| |
| @node IERRNO |
| @section @code{IERRNO} --- Get the last system error number |
| @fnindex IERRNO |
| @cindex system, error handling |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the last system error number, as given by the C @code{errno()} |
| function. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IERRNO()} |
| |
| @item @emph{Arguments}: |
| None. |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{See also}: |
| @ref{PERROR} |
| @end table |
| |
| |
| |
| @node INDEX |
| @section @code{INDEX} --- Position of a substring within a string |
| @fnindex INDEX |
| @cindex substring position |
| @cindex string, find substring |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the position of the start of the first occurrence of string |
| @var{SUBSTRING} as a substring in @var{STRING}, counting from one. If |
| @var{SUBSTRING} is not present in @var{STRING}, zero is returned. If |
| the @var{BACK} argument is present and true, the return value is the |
| start of the last occurrence rather than the first. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = INDEX(STRING, SUBSTRING [, BACK])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be a scalar @code{CHARACTER(*)}, with |
| @code{INTENT(IN)} |
| @item @var{SUBSTRING} @tab Shall be a scalar @code{CHARACTER(*)}, with |
| @code{INTENT(IN)} |
| @item @var{BACK} @tab (Optional) Shall be a scalar @code{LOGICAL(*)}, with |
| @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{See also}: |
| @ref{SCAN}, @ref{VERIFY} |
| @end table |
| |
| |
| |
| @node INT |
| @section @code{INT} --- Convert to integer type |
| @fnindex INT |
| @fnindex IFIX |
| @fnindex IDINT |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| Convert to integer type |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = INT(A [, KIND))} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| These functions return a @code{INTEGER(*)} variable or array under |
| the following rules: |
| |
| @table @asis |
| @item (A) |
| If @var{A} is of type @code{INTEGER(*)}, @code{INT(A) = A} |
| @item (B) |
| If @var{A} is of type @code{REAL(*)} and @math{|A| < 1}, @code{INT(A)} equals @code{0}. |
| If @math{|A| \geq 1}, then @code{INT(A)} equals the largest integer that does not exceed |
| the range of @var{A} and whose sign is the same as the sign of @var{A}. |
| @item (C) |
| If @var{A} is of type @code{COMPLEX(*)}, rule B is applied to the real part of @var{A}. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_int |
| integer :: i = 42 |
| complex :: z = (-3.7, 1.0) |
| print *, int(i) |
| print *, int(z), int(z,8) |
| end program |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{IFIX(A)} @tab @code{REAL(4) A} @tab @code{INTEGER} @tab F77 and later |
| @item @code{IDINT(A)} @tab @code{REAL(8) A} @tab @code{INTEGER} @tab F77 and later |
| @end multitable |
| |
| @end table |
| |
| |
| |
| @node INT2 |
| @section @code{INT2} --- Convert to 16-bit integer type |
| @fnindex INT2 |
| @fnindex SHORT |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| Convert to a @code{KIND=2} integer type. This is equivalent to the |
| standard @code{INT} intrinsic with an optional argument of |
| @code{KIND=2}, and is only included for backwards compatibility. |
| |
| The @code{SHORT} intrinsic is equivalent to @code{INT2}. |
| |
| @item @emph{Standard}: |
| GNU extension. |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = INT2(A)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a @code{INTEGER(2)} variable. |
| |
| @item @emph{See also}: |
| @ref{INT}, @ref{INT8}, @ref{LONG} |
| @end table |
| |
| |
| |
| @node INT8 |
| @section @code{INT8} --- Convert to 64-bit integer type |
| @fnindex INT8 |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| Convert to a @code{KIND=8} integer type. This is equivalent to the |
| standard @code{INT} intrinsic with an optional argument of |
| @code{KIND=8}, and is only included for backwards compatibility. |
| |
| @item @emph{Standard}: |
| GNU extension. |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = INT8(A)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a @code{INTEGER(8)} variable. |
| |
| @item @emph{See also}: |
| @ref{INT}, @ref{INT2}, @ref{LONG} |
| @end table |
| |
| |
| |
| @node IOR |
| @section @code{IOR} --- Bitwise logical or |
| @fnindex IOR |
| @cindex bitwise logical or |
| @cindex logical or, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IEOR} returns the bitwise boolean OR of @var{I} and |
| @var{J}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IEOR(I, J)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{J} @tab The type shall be @code{INTEGER(*)}, of the same |
| kind as @var{I}. (As a GNU extension, different kinds are also |
| permitted.) |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is @code{INTEGER(*)}, of the same kind as the |
| arguments. (If the argument kinds differ, it is of the same kind as |
| the larger argument.) |
| |
| @item @emph{See also}: |
| @ref{IEOR}, @ref{IAND}, @ref{IBITS}, @ref{IBSET}, @ref{IBCLR}, @ref{NOT} |
| @end table |
| |
| |
| |
| @node IRAND |
| @section @code{IRAND} --- Integer pseudo-random number |
| @fnindex IRAND |
| @cindex random number generation |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IRAND(FLAG)} returns a pseudo-random number from a uniform |
| distribution between 0 and a system-dependent limit (which is in most |
| cases 2147483647). If @var{FLAG} is 0, the next number |
| in the current sequence is returned; if @var{FLAG} is 1, the generator |
| is restarted by @code{CALL SRAND(0)}; if @var{FLAG} has any other value, |
| it is used as a new seed with @code{SRAND}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = IRAND(FLAG)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{FLAG} @tab Shall be a scalar @code{INTEGER} of kind 4. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of @code{INTEGER(kind=4)} type. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_irand |
| integer,parameter :: seed = 86456 |
| |
| call srand(seed) |
| print *, irand(), irand(), irand(), irand() |
| print *, irand(seed), irand(), irand(), irand() |
| end program test_irand |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node ISATTY |
| @section @code{ISATTY} --- Whether a unit is a terminal device. |
| @fnindex ISATTY |
| @cindex system, terminal |
| |
| @table @asis |
| @item @emph{Description}: |
| Determine whether a unit is connected to a terminal device. |
| |
| @item @emph{Standard}: |
| GNU extension. |
| |
| @item @emph{Class}: |
| Non-elemental function. |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ISATTY(UNIT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab Shall be a scalar @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @code{.TRUE.} if the @var{UNIT} is connected to a terminal |
| device, @code{.FALSE.} otherwise. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_isatty |
| INTEGER(kind=1) :: unit |
| DO unit = 1, 10 |
| write(*,*) isatty(unit=unit) |
| END DO |
| END PROGRAM |
| @end smallexample |
| @item @emph{See also}: |
| @ref{TTYNAM} |
| @end table |
| |
| |
| |
| @node ISHFT |
| @section @code{ISHFT} --- Shift bits |
| @fnindex ISHFT |
| @cindex bits, shift |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ISHFT} returns a value corresponding to @var{I} with all of the |
| bits shifted @var{SHIFT} places. A value of @var{SHIFT} greater than |
| zero corresponds to a left shift, a value of zero corresponds to no |
| shift, and a value less than zero corresponds to a right shift. If the |
| absolute value of @var{SHIFT} is greater than @code{BIT_SIZE(I)}, the |
| value is undefined. Bits shifted out from the left end or right end are |
| lost; zeros are shifted in from the opposite end. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ISHFT(I, SHIFT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{ISHFTC} |
| @end table |
| |
| |
| |
| @node ISHFTC |
| @section @code{ISHFTC} --- Shift bits circularly |
| @fnindex ISHFTC |
| @cindex bits, shift circular |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{ISHFTC} returns a value corresponding to @var{I} with the |
| rightmost @var{SIZE} bits shifted circularly @var{SHIFT} places; that |
| is, bits shifted out one end are shifted into the opposite end. A value |
| of @var{SHIFT} greater than zero corresponds to a left shift, a value of |
| zero corresponds to no shift, and a value less than zero corresponds to |
| a right shift. The absolute value of @var{SHIFT} must be less than |
| @var{SIZE}. If the @var{SIZE} argument is omitted, it is taken to be |
| equivalent to @code{BIT_SIZE(I)}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = ISHFTC(I, SHIFT [, SIZE])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{SIZE} @tab (Optional) The type shall be @code{INTEGER(*)}; |
| the value must be greater than zero and less than or equal to |
| @code{BIT_SIZE(I)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{ISHFT} |
| @end table |
| |
| |
| |
| @node ITIME |
| @section @code{ITIME} --- Get current local time subroutine (hour/minutes/seconds) |
| @fnindex ITIME |
| @cindex time, current |
| @cindex current time |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{IDATE(TARRAY)} Fills @var{TARRAY} with the numerical values at the |
| current local time. The hour (in the range 1-24), minute (in the range 1-60), |
| and seconds (in the range 1-60) appear in elements 1, 2, and 3 of @var{TARRAY}, |
| respectively. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL ITIME(TARRAY)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TARRAY} @tab The type shall be @code{INTEGER, DIMENSION(3)} |
| and the kind shall be the default integer kind. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Does not return. |
| |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_itime |
| integer, dimension(3) :: tarray |
| call itime(tarray) |
| print *, tarray(1) |
| print *, tarray(2) |
| print *, tarray(3) |
| end program test_itime |
| @end smallexample |
| @end table |
| |
| |
| |
| @node KILL |
| @section @code{KILL} --- Send a signal to a process |
| @fnindex KILL |
| |
| @table @asis |
| @item @emph{Description}: |
| @item @emph{Standard}: |
| Sends the signal specified by @var{SIGNAL} to the process @var{PID}. |
| See @code{kill(2)}. |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL KILL(PID, SIGNAL [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PID} @tab Shall be a scalar @code{INTEGER}, with |
| @code{INTENT(IN)} |
| @item @var{SIGNAL} @tab Shall be a scalar @code{INTEGER}, with |
| @code{INTENT(IN)} |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER(4)} or |
| @code{INTEGER(8)}. Returns 0 on success, or a |
| system-specific error code otherwise. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{ABORT}, @ref{EXIT} |
| @end table |
| |
| |
| |
| @node KIND |
| @section @code{KIND} --- Kind of an entity |
| @fnindex KIND |
| @cindex kind |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{KIND(X)} returns the kind value of the entity @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{K = KIND(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{LOGICAL}, @code{INTEGER}, |
| @code{REAL}, @code{COMPLEX} or @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER} and of the default |
| integer kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_kind |
| integer,parameter :: kc = kind(' ') |
| integer,parameter :: kl = kind(.true.) |
| |
| print *, "The default character kind is ", kc |
| print *, "The default logical kind is ", kl |
| end program test_kind |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node LBOUND |
| @section @code{LBOUND} --- Lower dimension bounds of an array |
| @fnindex LBOUND |
| @cindex array, lower bound |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the lower bounds of an array, or a single lower bound |
| along the @var{DIM} dimension. |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LBOUND(ARRAY [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array, of any type. |
| @item @var{DIM} @tab (Optional) Shall be a scalar @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, the result is an array of the lower bounds of |
| @var{ARRAY}. If @var{DIM} is present, the result is a scalar |
| corresponding to the lower bound of the array along that dimension. If |
| @var{ARRAY} is an expression rather than a whole array or array |
| structure component, or if it has a zero extent along the relevant |
| dimension, the lower bound is taken to be 1. |
| |
| @item @emph{See also}: |
| @ref{UBOUND} |
| @end table |
| |
| |
| |
| @node LEN |
| @section @code{LEN} --- Length of a character entity |
| @fnindex LEN |
| @cindex string, length |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the length of a character string. If @var{STRING} is an array, |
| the length of an element of @var{STRING} is returned. Note that |
| @var{STRING} need not be defined when this intrinsic is invoked, since |
| only the length, not the content, of @var{STRING} is needed. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{L = LEN(STRING)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be a scalar or array of type |
| @code{CHARACTER(*)}, with @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is an @code{INTEGER} of the default kind. |
| |
| @item @emph{See also}: |
| @ref{LEN_TRIM}, @ref{ADJUSTL}, @ref{ADJUSTR} |
| @end table |
| |
| |
| |
| @node LEN_TRIM |
| @section @code{LEN_TRIM} --- Length of a character entity without trailing blank characters |
| @fnindex LEN_TRIM |
| @cindex string, length, without trailing whitespace |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the length of a character string, ignoring any trailing blanks. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LEN_TRIM(STRING)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be a scalar of type @code{CHARACTER(*)}, |
| with @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is an @code{INTEGER} of the default kind. |
| |
| @item @emph{See also}: |
| @ref{LEN}, @ref{ADJUSTL}, @ref{ADJUSTR} |
| @end table |
| |
| |
| |
| @node LGE |
| @section @code{LGE} --- Lexical greater than or equal |
| @fnindex LGE |
| @cindex lexical comparison of strings |
| @cindex string, comparison |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines whether one string is lexically greater than or equal to |
| another string, where the two strings are interpreted as containing |
| ASCII character codes. If the String A and String B are not the same |
| length, the shorter is compared as if spaces were appended to it to form |
| a value that has the same length as the longer. |
| |
| In general, the lexical comparison intrinsics @code{LGE}, @code{LGT}, |
| @code{LLE}, and @code{LLT} differ from the corresponding intrinsic |
| operators @code{.GE.}, @code{.GT.}, @code{.LE.}, and @code{.LT.}, in |
| that the latter use the processor's character ordering (which is not |
| ASCII on some targets), whereas the former always use the ASCII |
| ordering. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LGE(STRING_A, STRING_B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING_A} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STRING_B} @tab Shall be of default @code{CHARACTER} type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @code{.TRUE.} if @code{STRING_A >= STRING_B}, and @code{.FALSE.} |
| otherwise, based on the ASCII ordering. |
| |
| @item @emph{See also}: |
| @ref{LGT}, @ref{LLE}, @ref{LLT} |
| @end table |
| |
| |
| |
| @node LGT |
| @section @code{LGT} --- Lexical greater than |
| @fnindex LGT |
| @cindex lexical comparison of strings |
| @cindex string, comparison |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines whether one string is lexically greater than another string, |
| where the two strings are interpreted as containing ASCII character |
| codes. If the String A and String B are not the same length, the |
| shorter is compared as if spaces were appended to it to form a value |
| that has the same length as the longer. |
| |
| In general, the lexical comparison intrinsics @code{LGE}, @code{LGT}, |
| @code{LLE}, and @code{LLT} differ from the corresponding intrinsic |
| operators @code{.GE.}, @code{.GT.}, @code{.LE.}, and @code{.LT.}, in |
| that the latter use the processor's character ordering (which is not |
| ASCII on some targets), whereas the former always use the ASCII |
| ordering. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LGT(STRING_A, STRING_B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING_A} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STRING_B} @tab Shall be of default @code{CHARACTER} type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @code{.TRUE.} if @code{STRING_A > STRING_B}, and @code{.FALSE.} |
| otherwise, based on the ASCII ordering. |
| |
| @item @emph{See also}: |
| @ref{LGE}, @ref{LLE}, @ref{LLT} |
| @end table |
| |
| |
| |
| @node LINK |
| @section @code{LINK} --- Create a hard link |
| @fnindex LINK |
| @cindex file system, create link |
| @cindex file system, hard link |
| |
| @table @asis |
| @item @emph{Description}: |
| Makes a (hard) link from file @var{PATH1} to @var{PATH2}. A null |
| character (@code{CHAR(0)}) can be used to mark the end of the names in |
| @var{PATH1} and @var{PATH2}; otherwise, trailing blanks in the file |
| names are ignored. If the @var{STATUS} argument is supplied, it |
| contains 0 on success or a nonzero error code upon return; see |
| @code{link(2)}. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL LINK(PATH1, PATH2 [, STATUS])} |
| @item @code{STATUS = LINK(PATH1, PATH2)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PATH1} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{PATH2} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STATUS} @tab (Optional) Shall be of default @code{INTEGER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{SYMLNK}, @ref{UNLINK} |
| @end table |
| |
| |
| |
| @node LLE |
| @section @code{LLE} --- Lexical less than or equal |
| @fnindex LLE |
| @cindex lexical comparison of strings |
| @cindex string, comparison |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines whether one string is lexically less than or equal to another |
| string, where the two strings are interpreted as containing ASCII |
| character codes. If the String A and String B are not the same length, |
| the shorter is compared as if spaces were appended to it to form a value |
| that has the same length as the longer. |
| |
| In general, the lexical comparison intrinsics @code{LGE}, @code{LGT}, |
| @code{LLE}, and @code{LLT} differ from the corresponding intrinsic |
| operators @code{.GE.}, @code{.GT.}, @code{.LE.}, and @code{.LT.}, in |
| that the latter use the processor's character ordering (which is not |
| ASCII on some targets), whereas the former always use the ASCII |
| ordering. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LLE(STRING_A, STRING_B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING_A} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STRING_B} @tab Shall be of default @code{CHARACTER} type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @code{.TRUE.} if @code{STRING_A <= STRING_B}, and @code{.FALSE.} |
| otherwise, based on the ASCII ordering. |
| |
| @item @emph{See also}: |
| @ref{LGE}, @ref{LGT}, @ref{LLT} |
| @end table |
| |
| |
| |
| @node LLT |
| @section @code{LLT} --- Lexical less than |
| @fnindex LLT |
| @cindex lexical comparison of strings |
| @cindex string, comparison |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines whether one string is lexically less than another string, |
| where the two strings are interpreted as containing ASCII character |
| codes. If the String A and String B are not the same length, the |
| shorter is compared as if spaces were appended to it to form a value |
| that has the same length as the longer. |
| |
| In general, the lexical comparison intrinsics @code{LGE}, @code{LGT}, |
| @code{LLE}, and @code{LLT} differ from the corresponding intrinsic |
| operators @code{.GE.}, @code{.GT.}, @code{.LE.}, and @code{.LT.}, in |
| that the latter use the processor's character ordering (which is not |
| ASCII on some targets), whereas the former always use the ASCII |
| ordering. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LLT(STRING_A, STRING_B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING_A} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STRING_B} @tab Shall be of default @code{CHARACTER} type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @code{.TRUE.} if @code{STRING_A < STRING_B}, and @code{.FALSE.} |
| otherwise, based on the ASCII ordering. |
| |
| @item @emph{See also}: |
| @ref{LGE}, @ref{LGT}, @ref{LLE} |
| @end table |
| |
| |
| |
| @node LNBLNK |
| @section @code{LNBLNK} --- Index of the last non-blank character in a string |
| @fnindex LNBLNK |
| @cindex string, find non-blank character |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the length of a character string, ignoring any trailing blanks. |
| This is identical to the standard @code{LEN_TRIM} intrinsic, and is only |
| included for backwards compatibility. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LNBLNK(STRING)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be a scalar of type @code{CHARACTER(*)}, |
| with @code{INTENT(IN)} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of @code{INTEGER(kind=4)} type. |
| |
| @item @emph{See also}: |
| @ref{INDEX}, @ref{LEN_TRIM} |
| @end table |
| |
| |
| |
| @node LOC |
| @section @code{LOC} --- Returns the address of a variable |
| @fnindex LOC |
| @cindex location of a variable in memory |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{LOC(X)} returns the address of @var{X} as an integer. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LOC(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Variable of any type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER}, with a @code{KIND} |
| corresponding to the size (in bytes) of a memory address on the target |
| machine. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_loc |
| integer :: i |
| real :: r |
| i = loc(r) |
| print *, i |
| end program test_loc |
| @end smallexample |
| @end table |
| |
| |
| |
| @node LOG |
| @section @code{LOG} --- Logarithm function |
| @fnindex LOG |
| @fnindex ALOG |
| @fnindex DLOG |
| @fnindex CLOG |
| @fnindex ZLOG |
| @fnindex CDLOG |
| @cindex exponential function, inverse |
| @cindex logarithmic function |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{LOG(X)} computes the logarithm of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LOG(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} or |
| @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} or @code{COMPLEX(*)}. |
| The kind type parameter is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_log |
| real(8) :: x = 1.0_8 |
| complex :: z = (1.0, 2.0) |
| x = log(x) |
| z = log(z) |
| end program test_log |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{ALOG(X)} @tab @code{REAL(4) X} @tab @code{REAL(4)} @tab f95, gnu |
| @item @code{DLOG(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab f95, gnu |
| @item @code{CLOG(X)} @tab @code{COMPLEX(4) X} @tab @code{COMPLEX(4)} @tab f95, gnu |
| @item @code{ZLOG(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab f95, gnu |
| @item @code{CDLOG(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab f95, gnu |
| @end multitable |
| @end table |
| |
| |
| |
| @node LOG10 |
| @section @code{LOG10} --- Base 10 logarithm function |
| @fnindex LOG10 |
| @fnindex ALOG10 |
| @fnindex DLOG10 |
| @cindex exponential function, inverse |
| @cindex logarithmic function |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{LOG10(X)} computes the base 10 logarithm of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LOG10(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} or @code{COMPLEX(*)}. |
| The kind type parameter is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_log10 |
| real(8) :: x = 10.0_8 |
| x = log10(x) |
| end program test_log10 |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{ALOG10(X)} @tab @code{REAL(4) X} @tab @code{REAL(4)} @tab F95 and later |
| @item @code{DLOG10(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node LOGICAL |
| @section @code{LOGICAL} --- Convert to logical type |
| @fnindex LOGICAL |
| @cindex conversion, to logical |
| |
| @table @asis |
| @item @emph{Description}: |
| Converts one kind of @code{LOGICAL} variable to another. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LOGICAL(L [, KIND])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{L} @tab The type shall be @code{LOGICAL(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a @code{LOGICAL} value equal to @var{L}, with a |
| kind corresponding to @var{KIND}, or of the default logical kind if |
| @var{KIND} is not given. |
| |
| @item @emph{See also}: |
| @ref{INT}, @ref{REAL}, @ref{CMPLX} |
| @end table |
| |
| |
| |
| @node LONG |
| @section @code{LONG} --- Convert to integer type |
| @fnindex LONG |
| @cindex conversion, to integer |
| |
| @table @asis |
| @item @emph{Description}: |
| Convert to a @code{KIND=4} integer type, which is the same size as a C |
| @code{long} integer. This is equivalent to the standard @code{INT} |
| intrinsic with an optional argument of @code{KIND=4}, and is only |
| included for backwards compatibility. |
| |
| @item @emph{Standard}: |
| GNU extension. |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LONG(A)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a @code{INTEGER(4)} variable. |
| |
| @item @emph{See also}: |
| @ref{INT}, @ref{INT2}, @ref{INT8} |
| @end table |
| |
| |
| |
| @node LSHIFT |
| @section @code{LSHIFT} --- Left shift bits |
| @fnindex LSHIFT |
| @cindex bits, shift left |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{LSHIFT} returns a value corresponding to @var{I} with all of the |
| bits shifted left by @var{SHIFT} places. If the absolute value of |
| @var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined. |
| Bits shifted out from the left end are lost; zeros are shifted in from |
| the opposite end. |
| |
| This function has been superseded by the @code{ISHFT} intrinsic, which |
| is standard in Fortran 95 and later. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = LSHIFT(I, SHIFT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{ISHFT}, @ref{ISHFTC}, @ref{RSHIFT} |
| |
| @end table |
| |
| |
| |
| @node LSTAT |
| @section @code{LSTAT} --- Get file status |
| @fnindex LSTAT |
| @cindex file system, file status |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{LSTAT} is identical to @ref{STAT}, except that if path is a symbolic link, |
| then the link itself is statted, not the file that it refers to. |
| |
| The elements in @code{BUFF} are the same as described by @ref{STAT}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL LSTAT(FILE, BUFF [, STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{FILE} @tab The type shall be @code{CHARACTER(*)}, a valid path within the file system. |
| @item @var{BUFF} @tab The type shall be @code{INTEGER(4), DIMENSION(13)}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER(4)}. Returns 0 |
| on success and a system specific error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| See @ref{STAT} for an example. |
| |
| @item @emph{See also}: |
| To stat an open file: @ref{FSTAT}, to stat a file: @ref{STAT} |
| @end table |
| |
| |
| |
| @node LTIME |
| @section @code{LTIME} --- Convert time to local time info |
| @fnindex LTIME |
| @cindex time, converstion to local time info |
| |
| @table @asis |
| @item @emph{Description}: |
| Given a system time value @var{STIME} (as provided by the @code{TIME8()} |
| intrinsic), fills @var{TARRAY} with values extracted from it appropriate |
| to the local time zone using @code{localtime(3)}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL LTIME(STIME, TARRAY)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STIME} @tab An @code{INTEGER(*)} scalar expression |
| corresponding to a system time, with |
| @code{INTENT(IN)}. |
| @item @var{TARRAY} @tab A default @code{INTEGER} array with 9 elements, |
| with @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The elements of @var{TARRAY} are assigned as follows: |
| @enumerate |
| @item Seconds after the minute, range 0--59 or 0--61 to allow for leap |
| seconds |
| @item Minutes after the hour, range 0--59 |
| @item Hours past midnight, range 0--23 |
| @item Day of month, range 0--31 |
| @item Number of months since January, range 0--12 |
| @item Years since 1900 |
| @item Number of days since Sunday, range 0--6 |
| @item Days since January 1 |
| @item Daylight savings indicator: positive if daylight savings is in |
| effect, zero if not, and negative if the information is not |
| available. |
| @end enumerate |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{GMTIME}, @ref{TIME}, @ref{TIME8} |
| |
| @end table |
| |
| |
| |
| @node MALLOC |
| @section @code{MALLOC} --- Allocate dynamic memory |
| @fnindex MALLOC |
| @cindex pointer, cray |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MALLOC(SIZE)} allocates @var{SIZE} bytes of dynamic memory and |
| returns the address of the allocated memory. The @code{MALLOC} intrinsic |
| is an extension intended to be used with Cray pointers, and is provided |
| in GNU Fortran to allow the user to compile legacy code. For new code |
| using Fortran 95 pointers, the memory allocation intrinsic is |
| @code{ALLOCATE}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{PTR = MALLOC(SIZE)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SIZE} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(K)}, with @var{K} such that |
| variables of type @code{INTEGER(K)} have the same size as |
| C pointers (@code{sizeof(void *)}). |
| |
| @item @emph{Example}: |
| The following example demonstrates the use of @code{MALLOC} and |
| @code{FREE} with Cray pointers. This example is intended to run on |
| 32-bit systems, where the default integer kind is suitable to store |
| pointers; on 64-bit systems, ptr_x would need to be declared as |
| @code{integer(kind=8)}. |
| |
| @smallexample |
| program test_malloc |
| integer i |
| integer ptr_x |
| real*8 x(*), z |
| pointer(ptr_x,x) |
| |
| ptr_x = malloc(20*8) |
| do i = 1, 20 |
| x(i) = sqrt(1.0d0 / i) |
| end do |
| z = 0 |
| do i = 1, 20 |
| z = z + x(i) |
| print *, z |
| end do |
| call free(ptr_x) |
| end program test_malloc |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{FREE} |
| @end table |
| |
| |
| |
| @node MATMUL |
| @section @code{MATMUL} --- matrix multiplication |
| @fnindex MATMUL |
| @cindex matrix multiplication |
| @cindex product, matrix |
| |
| @table @asis |
| @item @emph{Description}: |
| Performs a matrix multiplication on numeric or logical arguments. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MATMUL(MATRIX_A, MATRIX_B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MATRIX_A} @tab An array of @code{INTEGER(*)}, |
| @code{REAL(*)}, @code{COMPLEX(*)}, or |
| @code{LOGICAL(*)} type, with a rank of |
| one or two. |
| @item @var{MATRIX_B} @tab An array of @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{COMPLEX(*)} type if |
| @var{MATRIX_A} is of a numeric type; |
| otherwise, an array of @code{LOGICAL(*)} |
| type. The rank shall be one or two, and the |
| first (or only) dimension of @var{MATRIX_B} |
| shall be equal to the last (or only) |
| dimension of @var{MATRIX_A}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The matrix product of @var{MATRIX_A} and @var{MATRIX_B}. The type and |
| kind of the result follow the usual type and kind promotion rules, as |
| for the @code{*} or @code{.AND.} operators. |
| |
| @item @emph{See also}: |
| @end table |
| |
| |
| |
| @node MAX |
| @section @code{MAX} --- Maximum value of an argument list |
| @fnindex MAX |
| @fnindex MAX0 |
| @fnindex AMAX0 |
| @fnindex MAX1 |
| @fnindex AMAX1 |
| @fnindex DMAX1 |
| @cindex maximum value |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the argument with the largest (most positive) value. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MAX(A1, A2 [, A3 [, ...]])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A1} @tab The type shall be @code{INTEGER(*)} or |
| @code{REAL(*)}. |
| @item @var{A2}, @var{A3}, ... @tab An expression of the same type and kind |
| as @var{A1}. (As a GNU extension, |
| arguments of different kinds are |
| permitted.) |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value corresponds to the maximum value among the arguments, |
| and has the same type and kind as the first argument. |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{MAX0(I)} @tab @code{INTEGER(4) I} @tab @code{INTEGER(4)} @tab F77 and later |
| @item @code{AMAX0(I)} @tab @code{INTEGER(4) I} @tab @code{REAL(MAX(X))} @tab F77 and later |
| @item @code{MAX1(X)} @tab @code{REAL(*) X} @tab @code{INT(MAX(X))} @tab F77 and later |
| @item @code{AMAX1(X)} @tab @code{REAL(4) X} @tab @code{REAL(4)} @tab F77 and later |
| @item @code{DMAX1(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{MAXLOC} @ref{MAXVAL}, @ref{MIN} |
| |
| @end table |
| |
| |
| |
| @node MAXEXPONENT |
| @section @code{MAXEXPONENT} --- Maximum exponent of a real kind |
| @fnindex MAXEXPONENT |
| @cindex model representation, maximum exponent |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MAXEXPONENT(X)} returns the maximum exponent in the model of the |
| type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MAXEXPONENT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program exponents |
| real(kind=4) :: x |
| real(kind=8) :: y |
| |
| print *, minexponent(x), maxexponent(x) |
| print *, minexponent(y), maxexponent(y) |
| end program exponents |
| @end smallexample |
| @end table |
| |
| |
| |
| @node MAXLOC |
| @section @code{MAXLOC} --- Location of the maximum value within an array |
| @fnindex MAXLOC |
| @cindex array, location of maximum element |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the location of the element in the array with the maximum |
| value, or, if the @var{DIM} argument is supplied, determines the |
| locations of the maximum element along each row of the array in the |
| @var{DIM} direction. If @var{MASK} is present, only the elements for |
| which @var{MASK} is @code{.TRUE.} are considered. If more than one |
| element in the array has the maximum value, the location returned is |
| that of the first such element in array element order. If the array has |
| zero size, or all of the elements of @var{MASK} are @code{.FALSE.}, then |
| the result is an array of zeroes. Similarly, if @var{DIM} is supplied |
| and all of the elements of @var{MASK} along a given row are zero, the |
| result value for that row is zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{RESULT = MAXLOC(ARRAY, DIM [, MASK])} |
| @item @code{RESULT = MAXLOC(ARRAY [, MASK])} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{CHARACTER(*)}. |
| @item @var{DIM} @tab (Optional) Shall be a scalar of type |
| @code{INTEGER(*)}, with a value between one |
| and the rank of @var{ARRAY}, inclusive. It |
| may not be an optional dummy argument. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL(*)}, |
| and conformable with @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, the result is a rank-one array with a length |
| equal to the rank of @var{ARRAY}. If @var{DIM} is present, the result |
| is an array with a rank one less than the rank of @var{ARRAY}, and a |
| size corresponding to the size of @var{ARRAY} with the @var{DIM} |
| dimension removed. If @var{DIM} is present and @var{ARRAY} has a rank |
| of one, the result is a scalar. In all cases, the result is of default |
| @code{INTEGER} type. |
| |
| @item @emph{See also}: |
| @ref{MAX}, @ref{MAXVAL} |
| |
| @end table |
| |
| |
| |
| @node MAXVAL |
| @section @code{MAXVAL} --- Maximum value of an array |
| @fnindex MAXVAL |
| @cindex array, maximum value |
| @cindex maximum value |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the maximum value of the elements in an array value, or, if |
| the @var{DIM} argument is supplied, determines the maximum value along |
| each row of the array in the @var{DIM} direction. If @var{MASK} is |
| present, only the elements for which @var{MASK} is @code{.TRUE.} are |
| considered. If the array has zero size, or all of the elements of |
| @var{MASK} are @code{.FALSE.}, then the result is the most negative |
| number of the type and kind of @var{ARRAY} if @var{ARRAY} is numeric, or |
| a string of nulls if @var{ARRAY} is of character type. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{RESULT = MAXVAL(ARRAY, DIM [, MASK])} |
| @item @code{RESULT = MAXVAL(ARRAY [, MASK])} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{CHARACTER(*)}. |
| @item @var{DIM} @tab (Optional) Shall be a scalar of type |
| @code{INTEGER(*)}, with a value between one |
| and the rank of @var{ARRAY}, inclusive. It |
| may not be an optional dummy argument. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL(*)}, |
| and conformable with @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, or if @var{ARRAY} has a rank of one, the result |
| is a scalar. If @var{DIM} is present, the result is an array with a |
| rank one less than the rank of @var{ARRAY}, and a size corresponding to |
| the size of @var{ARRAY} with the @var{DIM} dimension removed. In all |
| cases, the result is of the same type and kind as @var{ARRAY}. |
| |
| @item @emph{See also}: |
| @ref{MAX}, @ref{MAXLOC} |
| @end table |
| |
| |
| |
| @node MCLOCK |
| @section @code{MCLOCK} --- Time function |
| @fnindex MCLOCK |
| @cindex time, clock ticks |
| @cindex clock ticks |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the number of clock ticks since the start of the process, based |
| on the UNIX function @code{clock(3)}. |
| |
| This intrinsic is not fully portable, such as to systems with 32-bit |
| @code{INTEGER} types but supporting times wider than 32 bits. Therefore, |
| the values returned by this intrinsic might be, or become, negative, or |
| numerically less than previous values, during a single run of the |
| compiled program. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MCLOCK()} |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER(4)}, equal to the |
| number of clock ticks since the start of the process, or @code{-1} if |
| the system does not support @code{clock(3)}. |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{GMTIME}, @ref{LTIME}, @ref{MCLOCK}, @ref{TIME} |
| |
| @end table |
| |
| |
| |
| @node MCLOCK8 |
| @section @code{MCLOCK8} --- Time function (64-bit) |
| @fnindex MCLOCK8 |
| @cindex time, clock ticks |
| @cindex clock ticks |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the number of clock ticks since the start of the process, based |
| on the UNIX function @code{clock(3)}. |
| |
| @emph{Warning:} this intrinsic does not increase the range of the timing |
| values over that returned by @code{clock(3)}. On a system with a 32-bit |
| @code{clock(3)}, @code{MCLOCK8()} will return a 32-bit value, even though |
| it is converted to a 64-bit @code{INTEGER(8)} value. That means |
| overflows of the 32-bit value can still occur. Therefore, the values |
| returned by this intrinsic might be or become negative or numerically |
| less than previous values during a single run of the compiled program. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MCLOCK8()} |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER(8)}, equal to the |
| number of clock ticks since the start of the process, or @code{-1} if |
| the system does not support @code{clock(3)}. |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{GMTIME}, @ref{LTIME}, @ref{MCLOCK}, @ref{TIME8} |
| |
| @end table |
| |
| |
| |
| @node MERGE |
| @section @code{MERGE} --- Merge variables |
| @fnindex MERGE |
| @cindex array, merge arrays |
| @cindex array, combine arrays |
| |
| @table @asis |
| @item @emph{Description}: |
| Select values from two arrays according to a logical mask. The result |
| is equal to @var{TSOURCE} if @var{MASK} is @code{.TRUE.}, or equal to |
| @var{FSOURCE} if it is @code{.FALSE.}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MERGE(TSOURCE, FSOURCE, MASK)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TSOURCE} @tab May be of any type. |
| @item @var{FSOURCE} @tab Shall be of the same type and type parameters |
| as @var{TSOURCE}. |
| @item @var{MASK} @tab Shall be of type @code{LOGICAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is of the same type and type parameters as @var{TSOURCE}. |
| |
| @end table |
| |
| |
| |
| @node MIN |
| @section @code{MIN} --- Minimum value of an argument list |
| @fnindex MIN |
| @fnindex MIN0 |
| @fnindex AMIN0 |
| @fnindex MIN1 |
| @fnindex AMIN1 |
| @fnindex DMIN1 |
| @cindex minimum value |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the argument with the smallest (most negative) value. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MIN(A1, A2 [, A3, ...])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A1} @tab The type shall be @code{INTEGER(*)} or |
| @code{REAL(*)}. |
| @item @var{A2}, @var{A3}, ... @tab An expression of the same type and kind |
| as @var{A1}. (As a GNU extension, |
| arguments of different kinds are |
| permitted.) |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value corresponds to the maximum value among the arguments, |
| and has the same type and kind as the first argument. |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{MIN0(I)} @tab @code{INTEGER(4) I} @tab @code{INTEGER(4)} @tab F77 and later |
| @item @code{AMIN0(I)} @tab @code{INTEGER(4) I} @tab @code{REAL(MIN(X))} @tab F77 and later |
| @item @code{MIN1(X)} @tab @code{REAL(*) X} @tab @code{INT(MIN(X))} @tab F77 and later |
| @item @code{AMIN1(X)} @tab @code{REAL(4) X} @tab @code{REAL(4)} @tab F77 and later |
| @item @code{DMIN1(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F77 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{MAX}, @ref{MINLOC}, @ref{MINVAL} |
| @end table |
| |
| |
| |
| @node MINEXPONENT |
| @section @code{MINEXPONENT} --- Minimum exponent of a real kind |
| @fnindex MINEXPONENT |
| @cindex model representation, minimum exponent |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MINEXPONENT(X)} returns the minimum exponent in the model of the |
| type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MINEXPONENT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| See @code{MAXEXPONENT} for an example. |
| @end table |
| |
| |
| |
| @node MINLOC |
| @section @code{MINLOC} --- Location of the minimum value within an array |
| @fnindex MINLOC |
| @cindex array, location of minimum element |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the location of the element in the array with the minimum |
| value, or, if the @var{DIM} argument is supplied, determines the |
| locations of the minimum element along each row of the array in the |
| @var{DIM} direction. If @var{MASK} is present, only the elements for |
| which @var{MASK} is @code{.TRUE.} are considered. If more than one |
| element in the array has the minimum value, the location returned is |
| that of the first such element in array element order. If the array has |
| zero size, or all of the elements of @var{MASK} are @code{.FALSE.}, then |
| the result is an array of zeroes. Similarly, if @var{DIM} is supplied |
| and all of the elements of @var{MASK} along a given row are zero, the |
| result value for that row is zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{RESULT = MINLOC(ARRAY, DIM [, MASK])} |
| @item @code{RESULT = MINLOC(ARRAY [, MASK])} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{CHARACTER(*)}. |
| @item @var{DIM} @tab (Optional) Shall be a scalar of type |
| @code{INTEGER(*)}, with a value between one |
| and the rank of @var{ARRAY}, inclusive. It |
| may not be an optional dummy argument. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL(*)}, |
| and conformable with @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, the result is a rank-one array with a length |
| equal to the rank of @var{ARRAY}. If @var{DIM} is present, the result |
| is an array with a rank one less than the rank of @var{ARRAY}, and a |
| size corresponding to the size of @var{ARRAY} with the @var{DIM} |
| dimension removed. If @var{DIM} is present and @var{ARRAY} has a rank |
| of one, the result is a scalar. In all cases, the result is of default |
| @code{INTEGER} type. |
| |
| @item @emph{See also}: |
| @ref{MIN}, @ref{MINVAL} |
| |
| @end table |
| |
| |
| |
| @node MINVAL |
| @section @code{MINVAL} --- Minimum value of an array |
| @fnindex MINVAL |
| @cindex array, minmum value |
| @cindex minimum value |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the minimum value of the elements in an array value, or, if |
| the @var{DIM} argument is supplied, determines the minimum value along |
| each row of the array in the @var{DIM} direction. If @var{MASK} is |
| present, only the elements for which @var{MASK} is @code{.TRUE.} are |
| considered. If the array has zero size, or all of the elements of |
| @var{MASK} are @code{.FALSE.}, then the result is @code{HUGE(ARRAY)} if |
| @var{ARRAY} is numeric, or a string of @code{CHAR(255)} characters if |
| @var{ARRAY} is of character type. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{RESULT = MINVAL(ARRAY, DIM [, MASK])} |
| @item @code{RESULT = MINVAL(ARRAY [, MASK])} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)}, or @code{CHARACTER(*)}. |
| @item @var{DIM} @tab (Optional) Shall be a scalar of type |
| @code{INTEGER(*)}, with a value between one |
| and the rank of @var{ARRAY}, inclusive. It |
| may not be an optional dummy argument. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL(*)}, |
| and conformable with @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, or if @var{ARRAY} has a rank of one, the result |
| is a scalar. If @var{DIM} is present, the result is an array with a |
| rank one less than the rank of @var{ARRAY}, and a size corresponding to |
| the size of @var{ARRAY} with the @var{DIM} dimension removed. In all |
| cases, the result is of the same type and kind as @var{ARRAY}. |
| |
| @item @emph{See also}: |
| @ref{MIN}, @ref{MINLOC} |
| |
| @end table |
| |
| |
| |
| @node MOD |
| @section @code{MOD} --- Remainder function |
| @fnindex MOD |
| @fnindex AMOD |
| @fnindex DMOD |
| @cindex remainder |
| @cindex division, remainder |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MOD(A,P)} computes the remainder of the division of A by P. It is |
| calculated as @code{A - (INT(A/P) * P)}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MOD(A, P)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be a scalar of type @code{INTEGER} or @code{REAL} |
| @item @var{P} @tab Shall be a scalar of the same type as @var{A} and not |
| equal to zero |
| @end multitable |
| |
| @item @emph{Return value}: |
| The kind of the return value is the result of cross-promoting |
| the kinds of the arguments. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_mod |
| print *, mod(17,3) |
| print *, mod(17.5,5.5) |
| print *, mod(17.5d0,5.5) |
| print *, mod(17.5,5.5d0) |
| |
| print *, mod(-17,3) |
| print *, mod(-17.5,5.5) |
| print *, mod(-17.5d0,5.5) |
| print *, mod(-17.5,5.5d0) |
| |
| print *, mod(17,-3) |
| print *, mod(17.5,-5.5) |
| print *, mod(17.5d0,-5.5) |
| print *, mod(17.5,-5.5d0) |
| end program test_mod |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Arguments @tab Return type @tab Standard |
| @item @code{AMOD(A,P)} @tab @code{REAL(4)} @tab @code{REAL(4)} @tab F95 and later |
| @item @code{DMOD(A,P)} @tab @code{REAL(8)} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| @end table |
| |
| |
| |
| @node MODULO |
| @section @code{MODULO} --- Modulo function |
| @fnindex MODULO |
| @cindex modulo |
| @cindex division, modulo |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MODULO(A,P)} computes the @var{A} modulo @var{P}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MODULO(A, P)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be a scalar of type @code{INTEGER} or @code{REAL} |
| @item @var{P} @tab Shall be a scalar of the same type and kind as @var{A} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The type and kind of the result are those of the arguments. |
| @table @asis |
| @item If @var{A} and @var{P} are of type @code{INTEGER}: |
| @code{MODULO(A,P)} has the value @var{R} such that @code{A=Q*P+R}, where |
| @var{Q} is an integer and @var{R} is between 0 (inclusive) and @var{P} |
| (exclusive). |
| @item If @var{A} and @var{P} are of type @code{REAL}: |
| @code{MODULO(A,P)} has the value of @code{A - FLOOR (A / P) * P}. |
| @end table |
| In all cases, if @var{P} is zero the result is processor-dependent. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_modulo |
| print *, modulo(17,3) |
| print *, modulo(17.5,5.5) |
| |
| print *, modulo(-17,3) |
| print *, modulo(-17.5,5.5) |
| |
| print *, modulo(17,-3) |
| print *, modulo(17.5,-5.5) |
| end program |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node MOVE_ALLOC |
| @section @code{MOVE_ALLOC} --- Move allocation from one object to another |
| @fnindex MOVE_ALLOC |
| @cindex moving allocation |
| @cindex allocation, moving |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{MOVE_ALLOC(SRC, DEST)} moves the allocation from @var{SRC} to |
| @var{DEST}. @var{SRC} will become deallocated in the process. |
| |
| @item @emph{Standard}: |
| F2003 and later |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL MOVE_ALLOC(SRC, DEST)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SRC} @tab @code{ALLOCATABLE}, @code{INTENT(INOUT)}, may be |
| of any type and kind. |
| @item @var{DEST} @tab @code{ALLOCATABLE}, @code{INTENT(OUT)}, shall be |
| of the same type, kind and rank as @var{SRC} |
| @end multitable |
| |
| @item @emph{Return value}: |
| None |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_move_alloc |
| integer, allocatable :: a(:), b(:) |
| |
| allocate(a(3)) |
| a = [ 1, 2, 3 ] |
| call move_alloc(a, b) |
| print *, allocated(a), allocated(b) |
| print *, b |
| end program test_move_alloc |
| @end smallexample |
| @end table |
| |
| |
| |
| @node MVBITS |
| @section @code{MVBITS} --- Move bits from one integer to another |
| @fnindex MVBITS |
| @cindex bits, move |
| |
| @table @asis |
| @item @emph{Description}: |
| Moves @var{LEN} bits from positions @var{FROMPOS} through |
| @code{FROMPOS+LEN-1} of @var{FROM} to positions @var{TOPOS} through |
| @code{TOPOS+LEN-1} of @var{TO}. The portion of argument @var{TO} not |
| affected by the movement of bits is unchanged. The values of |
| @code{FROMPOS+LEN-1} and @code{TOPOS+LEN-1} must be less than |
| @code{BIT_SIZE(FROM)}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = MVBITS(FROM, FROMPOS, LEN, TO, TOPOS)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{FROM} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{FROMPOS} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{LEN} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{TO} @tab The type shall be @code{INTEGER(*)}, of the |
| same kind as @var{FROM}. |
| @item @var{TOPOS} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{FROM}. |
| |
| @item @emph{See also}: |
| @ref{IBCLR}, @ref{IBSET}, @ref{IBITS}, @ref{IAND}, @ref{IOR}, @ref{IEOR} |
| |
| @end table |
| |
| |
| |
| @node NEAREST |
| @section @code{NEAREST} --- Nearest representable number |
| @fnindex NEAREST |
| @cindex real number, nearest different |
| @cindex floating point, nearest different |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{NEAREST(X, S)} returns the processor-representable number nearest |
| to @code{X} in the direction indicated by the sign of @code{S}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = NEAREST(X, S)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @item @var{S} @tab (Optional) shall be of type @code{REAL} and |
| not equal to zero. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type as @code{X}. If @code{S} is |
| positive, @code{NEAREST} returns the processor-representable number |
| greater than @code{X} and nearest to it. If @code{S} is negative, |
| @code{NEAREST} returns the processor-representable number smaller than |
| @code{X} and nearest to it. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_nearest |
| real :: x, y |
| x = nearest(42.0, 1.0) |
| y = nearest(42.0, -1.0) |
| write (*,"(3(G20.15))") x, y, x - y |
| end program test_nearest |
| @end smallexample |
| @end table |
| |
| |
| |
| @node NEW_LINE |
| @section @code{NEW_LINE} --- New line character |
| @fnindex NEW_LINE |
| @cindex newline |
| @cindex output, newline |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{NEW_LINE(C)} returns the new-line character. |
| |
| @item @emph{Standard}: |
| F2003 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = NEW_LINE(C)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{C} @tab The argument shall be a scalar or array of the |
| type @code{CHARACTER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns a @var{CHARACTER} scalar of length one with the new-line character of |
| the same kind as parameter @var{C}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program newline |
| implicit none |
| write(*,'(A)') 'This is record 1.'//NEW_LINE('A')//'This is record 2.' |
| end program newline |
| @end smallexample |
| @end table |
| |
| |
| |
| @node NINT |
| @section @code{NINT} --- Nearest whole number |
| @fnindex NINT |
| @fnindex IDNINT |
| @cindex rounding, nearest whole number |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{NINT(X)} rounds its argument to the nearest whole number. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = NINT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns @var{A} with the fractional portion of its magnitude eliminated by |
| rounding to the nearest whole number and with its sign preserved, |
| converted to an @code{INTEGER} of the default kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_nint |
| real(4) x4 |
| real(8) x8 |
| x4 = 1.234E0_4 |
| x8 = 4.321_8 |
| print *, nint(x4), idnint(x8) |
| end program test_nint |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .25 .25 .25 |
| @item Name @tab Argument @tab Standard |
| @item @code{IDNINT(X)} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{CEILING}, @ref{FLOOR} |
| |
| @end table |
| |
| |
| |
| @node NOT |
| @section @code{NOT} --- Logical negation |
| @fnindex NOT |
| @cindex bits, negate |
| @cindex bitwise logical not |
| @cindex logical not, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{NOT} returns the bitwise boolean inverse of @var{I}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = NOT(I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is @code{INTEGER(*)}, of the same kind as the |
| argument. |
| |
| @item @emph{See also}: |
| @ref{IAND}, @ref{IEOR}, @ref{IOR}, @ref{IBITS}, @ref{IBSET}, @ref{IBCLR} |
| |
| @end table |
| |
| |
| |
| @node NULL |
| @section @code{NULL} --- Function that returns an disassociated pointer |
| @fnindex NULL |
| @cindex pointer, status |
| @cindex pointer, disassociated |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns a disassociated pointer. |
| |
| If @var{MOLD} is present, a dissassociated pointer of the same type is |
| returned, otherwise the type is determined by context. |
| |
| In Fortran 95, @var{MOLD} is optional. Please note that F2003 includes |
| cases where it is required. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{PTR => NULL([MOLD])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MOLD} @tab (Optional) shall be a pointer of any association |
| status and of any type. |
| @end multitable |
| |
| @item @emph{Return value}: |
| A disassociated pointer. |
| |
| @item @emph{Example}: |
| @smallexample |
| REAL, POINTER, DIMENSION(:) :: VEC => NULL () |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ASSOCIATED} |
| @end table |
| |
| |
| |
| @node OR |
| @section @code{OR} --- Bitwise logical OR |
| @fnindex OR |
| @cindex bitwise logical or |
| @cindex logical or, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| Bitwise logical @code{OR}. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. For integer arguments, programmers should consider |
| the use of the @ref{IOR} intrinsic defined by the Fortran standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = OR(X, Y)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @item @var{Y} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is either @code{INTEGER(*)} or @code{LOGICAL} |
| after cross-promotion of the arguments. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_or |
| LOGICAL :: T = .TRUE., F = .FALSE. |
| INTEGER :: a, b |
| DATA a / Z'F' /, b / Z'3' / |
| |
| WRITE (*,*) OR(T, T), OR(T, F), OR(F, T), OR(F, F) |
| WRITE (*,*) OR(a, b) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| F95 elemental function: @ref{IOR} |
| @end table |
| |
| |
| |
| @node PACK |
| @section @code{PACK} --- Pack an array into an array of rank one |
| @fnindex PACK |
| @cindex array, packing |
| @cindex array, reduce dimension |
| @cindex array, gather elements |
| |
| @table @asis |
| @item @emph{Description}: |
| Stores the elements of @var{ARRAY} in an array of rank one. |
| |
| The beginning of the resulting array is made up of elements whose @var{MASK} |
| equals @code{TRUE}. Afterwards, positions are filled with elements taken from |
| @var{VECTOR}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = PACK(ARRAY, MASK[,VECTOR]} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of any type. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL} and |
| of the same size as @var{ARRAY}. Alternatively, it may be a @code{LOGICAL} |
| scalar. |
| @item @var{VECTOR} @tab (Optional) shall be an array of the same type |
| as @var{ARRAY} and of rank one. If present, the number of elements in |
| @var{VECTOR} shall be equal to or greater than the number of true elements |
| in @var{MASK}. If @var{MASK} is scalar, the number of elements in |
| @var{VECTOR} shall be equal to or greater than the number of elements in |
| @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is an array of rank one and the same type as that of @var{ARRAY}. |
| If @var{VECTOR} is present, the result size is that of @var{VECTOR}, the |
| number of @code{TRUE} values in @var{MASK} otherwise. |
| |
| @item @emph{Example}: |
| Gathering non-zero elements from an array: |
| @smallexample |
| PROGRAM test_pack_1 |
| INTEGER :: m(6) |
| m = (/ 1, 0, 0, 0, 5, 0 /) |
| WRITE(*, FMT="(6(I0, ' '))") pack(m, m /= 0) ! "1 5" |
| END PROGRAM |
| @end smallexample |
| |
| Gathering non-zero elements from an array and appending elements from @var{VECTOR}: |
| @smallexample |
| PROGRAM test_pack_2 |
| INTEGER :: m(4) |
| m = (/ 1, 0, 0, 2 /) |
| WRITE(*, FMT="(4(I0, ' '))") pack(m, m /= 0, (/ 0, 0, 3, 4 /)) ! "1 2 3 4" |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{UNPACK} |
| @end table |
| |
| |
| |
| @node PERROR |
| @section @code{PERROR} --- Print system error message |
| @fnindex PERROR |
| @cindex system, error handling |
| |
| @table @asis |
| @item @emph{Description}: |
| Prints (on the C @code{stderr} stream) a newline-terminated error |
| message corresponding to the last system error. This is prefixed by |
| @var{STRING}, a colon and a space. See @code{perror(3)}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL PERROR(STRING)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab A scalar of default @code{CHARACTER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{IERRNO} |
| @end table |
| |
| |
| |
| @node PRECISION |
| @section @code{PRECISION} --- Decimal precision of a real kind |
| @fnindex PRECISION |
| @cindex model representation, precision |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{PRECISION(X)} returns the decimal precision in the model of the |
| type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = PRECISION(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL} or @code{COMPLEX}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program prec_and_range |
| real(kind=4) :: x(2) |
| complex(kind=8) :: y |
| |
| print *, precision(x), range(x) |
| print *, precision(y), range(y) |
| end program prec_and_range |
| @end smallexample |
| @end table |
| |
| |
| |
| @node PRESENT |
| @section @code{PRESENT} --- Determine whether an optional dummy argument is specified |
| @fnindex PRESENT |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines whether an optional dummy argument is present. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = PRESENT(A)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab May be of any type and may be a pointer, scalar or array |
| value, or a dummy procedure. It shall be the name of an optional dummy argument |
| accessible within the current subroutine or function. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Returns either @code{TRUE} if the optional argument @var{A} is present, or |
| @code{FALSE} otherwise. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_present |
| WRITE(*,*) f(), f(42) ! "F T" |
| CONTAINS |
| LOGICAL FUNCTION f(x) |
| INTEGER, INTENT(IN), OPTIONAL :: x |
| f = PRESENT(x) |
| END FUNCTION |
| END PROGRAM |
| @end smallexample |
| @end table |
| |
| |
| |
| @node PRODUCT |
| @section @code{PRODUCT} --- Product of array elements |
| @fnindex PRODUCT |
| @cindex array, product |
| @cindex array, multiply elements |
| @cindex array, conditionally multiply elements |
| @cindex multiply array elements |
| |
| @table @asis |
| @item @emph{Description}: |
| Multiplies the elements of @var{ARRAY} along dimension @var{DIM} if |
| the corresponding element in @var{MASK} is @code{TRUE}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = PRODUCT(ARRAY[, MASK])} |
| @code{RESULT = PRODUCT(ARRAY, DIM[, MASK])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)} or @code{COMPLEX(*)}. |
| @item @var{DIM} @tab (Optional) shall be a scalar of type |
| @code{INTEGER} with a value in the range from 1 to n, where n |
| equals the rank of @var{ARRAY}. |
| @item @var{MASK} @tab (Optional) shall be of type @code{LOGICAL} |
| and either be a scalar or an array of the same shape as @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is of the same type as @var{ARRAY}. |
| |
| If @var{DIM} is absent, a scalar with the product of all elements in |
| @var{ARRAY} is returned. Otherwise, an array of rank n-1, where n equals |
| the rank of @var{ARRAY}, and a shape similar to that of @var{ARRAY} with |
| dimension @var{DIM} dropped is returned. |
| |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_product |
| INTEGER :: x(5) = (/ 1, 2, 3, 4 ,5 /) |
| print *, PRODUCT(x) ! all elements, product = 120 |
| print *, PRODUCT(x, MASK=MOD(x, 2)==1) ! odd elements, product = 15 |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SUM} |
| @end table |
| |
| |
| |
| @node RADIX |
| @section @code{RADIX} --- Base of a model number |
| @fnindex RADIX |
| @cindex model representation, base |
| @cindex model representation, radix |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{RADIX(X)} returns the base of the model representing the entity @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RADIX(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{INTEGER} or @code{REAL} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER} and of the default |
| integer kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_radix |
| print *, "The radix for the default integer kind is", radix(0) |
| print *, "The radix for the default real kind is", radix(0.0) |
| end program test_radix |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node RAN |
| @section @code{RAN} --- Real pseudo-random number |
| @fnindex RAN |
| @cindex random number generation |
| |
| @table @asis |
| @item @emph{Description}: |
| For compatibility with HP FORTRAN 77/iX, the @code{RAN} intrinsic is |
| provided as an alias for @code{RAND}. See @ref{RAND} for complete |
| documentation. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{See also}: |
| @ref{RAND}, @ref{RANDOM_NUMBER} |
| @end table |
| |
| |
| |
| @node RAND |
| @section @code{RAND} --- Real pseudo-random number |
| @fnindex RAND |
| @cindex random number generation |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{RAND(FLAG)} returns a pseudo-random number from a uniform |
| distribution between 0 and 1. If @var{FLAG} is 0, the next number |
| in the current sequence is returned; if @var{FLAG} is 1, the generator |
| is restarted by @code{CALL SRAND(0)}; if @var{FLAG} has any other value, |
| it is used as a new seed with @code{SRAND}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RAND(FLAG)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{FLAG} @tab Shall be a scalar @code{INTEGER} of kind 4. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of @code{REAL} type and the default kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_rand |
| integer,parameter :: seed = 86456 |
| |
| call srand(seed) |
| print *, rand(), rand(), rand(), rand() |
| print *, rand(seed), rand(), rand(), rand() |
| end program test_rand |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SRAND}, @ref{RANDOM_NUMBER} |
| |
| @end table |
| |
| |
| |
| @node RANDOM_NUMBER |
| @section @code{RANDOM_NUMBER} --- Pseudo-random number |
| @fnindex RANDOM_NUMBER |
| @cindex random number generation |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns a single pseudorandom number or an array of pseudorandom numbers |
| from the uniform distribution over the range @math{ 0 \leq x < 1}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{RANDOM_NUMBER(HARVEST)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{HARVEST} @tab Shall be a scalar or an array of type @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_random_number |
| REAL :: r(5,5) |
| CALL init_random_seed() ! see example of RANDOM_SEED |
| CALL RANDOM_NUMBER(r) |
| end program |
| @end smallexample |
| |
| @item @emph{Note}: |
| The implemented random number generator is thread safe if used within |
| OpenMP directives, i. e. its state will be consistent while called from |
| multiple threads. Please note that the currently implemented KISS generator |
| does not create random numbers in parallel from multiple sources, but in |
| sequence from a single source. If your OpenMP-enabled application heavily |
| relies on random numbers, you should consider employing a dedicated parallel |
| random number generator instead. |
| |
| @item @emph{See also}: |
| @ref{RANDOM_SEED} |
| @end table |
| |
| |
| |
| @node RANDOM_SEED |
| @section @code{RANDOM_SEED} --- Initialize a pseudo-random number sequence |
| @fnindex RANDOM_SEED |
| @cindex random number generation, seeding |
| @cindex seeding a random number generator |
| |
| @table @asis |
| @item @emph{Description}: |
| Restarts or queries the state of the pseudorandom number generator used by |
| @code{RANDOM_NUMBER}. |
| |
| If @code{RANDOM_SEED} is called without arguments, it is initialized to |
| a default state. The example below shows how to initialize the random |
| seed based on the system's time. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL RANDOM_SEED(SIZE, PUT, GET)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SIZE} @tab (Optional) Shall be a scalar and of type default |
| @code{INTEGER}, with @code{INTENT(OUT)}. It specifies the minimum size |
| of the arrays used with the @var{PUT} and @var{GET} arguments. |
| @item @var{PUT} @tab (Optional) Shall be an array of type default |
| @code{INTEGER} and rank one. It is @code{INTENT(IN)} and the size of |
| the array must be larger than or equal to the number returned by the |
| @var{SIZE} argument. |
| @item @var{GET} @tab (Optional) Shall be an array of type default |
| @code{INTEGER} and rank one. It is @code{INTENT(OUT)} and the size |
| of the array must be larger than or equal to the number returned by |
| the @var{SIZE} argument. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| SUBROUTINE init_random_seed() |
| INTEGER :: i, n, clock |
| INTEGER, DIMENSION(:), ALLOCATABLE :: seed |
| |
| CALL RANDOM_SEED(size = n) |
| ALLOCATE(seed(n)) |
| |
| CALL SYSTEM_CLOCK(COUNT=clock) |
| |
| seed = clock + 37 * (/ (i - 1, i = 1, n) /) |
| CALL RANDOM_SEED(PUT = seed) |
| |
| DEALLOCATE(seed) |
| END SUBROUTINE |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{RANDOM_NUMBER} |
| @end table |
| |
| |
| |
| @node RANGE |
| @section @code{RANGE} --- Decimal exponent range of a real kind |
| @fnindex RANGE |
| @cindex model representation, range |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{RANGE(X)} returns the decimal exponent range in the model of the |
| type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RANGE(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL} or @code{COMPLEX}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default integer |
| kind. |
| |
| @item @emph{Example}: |
| See @code{PRECISION} for an example. |
| @end table |
| |
| |
| |
| @node REAL |
| @section @code{REAL} --- Convert to real type |
| @fnindex REAL |
| @fnindex REALPART |
| @cindex conversion, to real |
| @cindex complex numbers, real part |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{REAL(X [, KIND])} converts its argument @var{X} to a real type. The |
| @code{REALPART(X)} function is provided for compatibility with @command{g77}, |
| and its use is strongly discouraged. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{RESULT = REAL(X [, KIND])} |
| @item @code{RESULT = REALPART(Z)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be @code{INTEGER(*)}, @code{REAL(*)}, or |
| @code{COMPLEX(*)}. |
| @item @var{KIND} @tab (Optional) An @code{INTEGER(*)} initialization |
| expression indicating the kind parameter of |
| the result. |
| @end multitable |
| |
| @item @emph{Return value}: |
| These functions return a @code{REAL(*)} variable or array under |
| the following rules: |
| |
| @table @asis |
| @item (A) |
| @code{REAL(X)} is converted to a default real type if @var{X} is an |
| integer or real variable. |
| @item (B) |
| @code{REAL(X)} is converted to a real type with the kind type parameter |
| of @var{X} if @var{X} is a complex variable. |
| @item (C) |
| @code{REAL(X, KIND)} is converted to a real type with kind type |
| parameter @var{KIND} if @var{X} is a complex, integer, or real |
| variable. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_real |
| complex :: x = (1.0, 2.0) |
| print *, real(x), real(x,8), realpart(x) |
| end program test_real |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{DBLE}, @ref{DFLOAT}, @ref{FLOAT} |
| |
| @end table |
| |
| |
| |
| @node RENAME |
| @section @code{RENAME} --- Rename a file |
| @fnindex RENAME |
| @cindex file system, rename file |
| |
| @table @asis |
| @item @emph{Description}: |
| Renames a file from file @var{PATH1} to @var{PATH2}. A null |
| character (@code{CHAR(0)}) can be used to mark the end of the names in |
| @var{PATH1} and @var{PATH2}; otherwise, trailing blanks in the file |
| names are ignored. If the @var{STATUS} argument is supplied, it |
| contains 0 on success or a nonzero error code upon return; see |
| @code{rename(2)}. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL RENAME(PATH1, PATH2 [, STATUS])} |
| @item @code{STATUS = RENAME(PATH1, PATH2)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PATH1} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{PATH2} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STATUS} @tab (Optional) Shall be of default @code{INTEGER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{LINK} |
| |
| @end table |
| |
| |
| |
| @node REPEAT |
| @section @code{REPEAT} --- Repeated string concatenation |
| @fnindex REPEAT |
| @cindex string, repeat |
| @cindex string, concatenate |
| |
| @table @asis |
| @item @emph{Description}: |
| Concatenates @var{NCOPIES} copies of a string. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = REPEAT(STRING, NCOPIES)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be scalar and of type @code{CHARACTER(*)}. |
| @item @var{NCOPIES} @tab Shall be scalar and of type @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| A new scalar of type @code{CHARACTER} built up from @var{NCOPIES} copies |
| of @var{STRING}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_repeat |
| write(*,*) repeat("x", 5) ! "xxxxx" |
| end program |
| @end smallexample |
| @end table |
| |
| |
| |
| @node RESHAPE |
| @section @code{RESHAPE} --- Function to reshape an array |
| @fnindex RESHAPE |
| @cindex array, change dimensions |
| @cindex array, transmogrify |
| |
| @table @asis |
| @item @emph{Description}: |
| Reshapes @var{SOURCE} to correspond to @var{SHAPE}. If necessary, |
| the new array may be padded with elements from @var{PAD} or permuted |
| as defined by @var{ORDER}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RESHAPE(SOURCE, SHAPE[, PAD, ORDER])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SOURCE} @tab Shall be an array of any type. |
| @item @var{SHAPE} @tab Shall be of type @code{INTEGER} and an |
| array of rank one. Its values must be positive or zero. |
| @item @var{PAD} @tab (Optional) shall be an array of the same |
| type as @var{SOURCE}. |
| @item @var{ORDER} @tab (Optional) shall be of type @code{INTEGER} |
| and an array of the same shape as @var{SHAPE}. Its values shall |
| be a permutation of the numbers from 1 to n, where n is the size of |
| @var{SHAPE}. If @var{ORDER} is absent, the natural ordering shall |
| be assumed. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is an array of shape @var{SHAPE} with the same type as |
| @var{SOURCE}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_reshape |
| INTEGER, DIMENSION(4) :: x |
| WRITE(*,*) SHAPE(x) ! prints "4" |
| WRITE(*,*) SHAPE(RESHAPE(x, (/2, 2/))) ! prints "2 2" |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SHAPE} |
| @end table |
| |
| |
| |
| @node RRSPACING |
| @section @code{RRSPACING} --- Reciprocal of the relative spacing |
| @fnindex RRSPACING |
| @cindex real number, relative spacing |
| @cindex floating point, relative spacing |
| |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{RRSPACING(X)} returns the reciprocal of the relative spacing of |
| model numbers near @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RRSPACING(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as @var{X}. |
| The value returned is equal to |
| @code{ABS(FRACTION(X)) * FLOAT(RADIX(X))**DIGITS(X)}. |
| |
| @item @emph{See also}: |
| @ref{SPACING} |
| @end table |
| |
| |
| |
| @node RSHIFT |
| @section @code{RSHIFT} --- Right shift bits |
| @fnindex RSHIFT |
| @cindex bits, shift right |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{RSHIFT} returns a value corresponding to @var{I} with all of the |
| bits shifted right by @var{SHIFT} places. If the absolute value of |
| @var{SHIFT} is greater than @code{BIT_SIZE(I)}, the value is undefined. |
| Bits shifted out from the left end are lost; zeros are shifted in from |
| the opposite end. |
| |
| This function has been superseded by the @code{ISHFT} intrinsic, which |
| is standard in Fortran 95 and later. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = RSHIFT(I, SHIFT)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab The type shall be @code{INTEGER(*)}. |
| @item @var{SHIFT} @tab The type shall be @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER(*)} and of the same kind as |
| @var{I}. |
| |
| @item @emph{See also}: |
| @ref{ISHFT}, @ref{ISHFTC}, @ref{LSHIFT} |
| |
| @end table |
| |
| |
| |
| @node SCALE |
| @section @code{SCALE} --- Scale a real value |
| @fnindex SCALE |
| @cindex real number, scale |
| @cindex floating point, scale |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SCALE(X,I)} returns @code{X * RADIX(X)**I}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SCALE(X, I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type of the argument shall be a @code{REAL}. |
| @item @var{I} @tab The type of the argument shall be a @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as @var{X}. |
| Its value is @code{X * RADIX(X)**I}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_scale |
| real :: x = 178.1387e-4 |
| integer :: i = 5 |
| print *, scale(x,i), x*radix(x)**i |
| end program test_scale |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node SCAN |
| @section @code{SCAN} --- Scan a string for the presence of a set of characters |
| @fnindex SCAN |
| @cindex string, find subset |
| |
| @table @asis |
| @item @emph{Description}: |
| Scans a @var{STRING} for any of the characters in a @var{SET} |
| of characters. |
| |
| If @var{BACK} is either absent or equals @code{FALSE}, this function |
| returns the position of the leftmost character of @var{STRING} that is |
| in @var{SET}. If @var{BACK} equals @code{TRUE}, the rightmost position |
| is returned. If no character of @var{SET} is found in @var{STRING}, the |
| result is zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SCAN(STRING, SET[, BACK])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{SET} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{BACK} @tab (Optional) shall be of type @code{LOGICAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default |
| integer kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_scan |
| WRITE(*,*) SCAN("FORTRAN", "AO") ! 2, found 'O' |
| WRITE(*,*) SCAN("FORTRAN", "AO", .TRUE.) ! 6, found 'A' |
| WRITE(*,*) SCAN("FORTRAN", "C++") ! 0, found none |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{INDEX}, @ref{VERIFY} |
| @end table |
| |
| |
| |
| @node SECNDS |
| @section @code{SECNDS} --- Time function |
| @fnindex SECNDS |
| @cindex time, elapsed |
| @cindex elapsed time |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SECNDS(X)} gets the time in seconds from the real-time system clock. |
| @var{X} is a reference time, also in seconds. If this is zero, the time in |
| seconds from midnight is returned. This function is non-standard and its |
| use is discouraged. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SECNDS (X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{T} @tab Shall be of type @code{REAL(4)}. |
| @item @var{X} @tab Shall be of type @code{REAL(4)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| None |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_secnds |
| integer :: i |
| real(4) :: t1, t2 |
| print *, secnds (0.0) ! seconds since midnight |
| t1 = secnds (0.0) ! reference time |
| do i = 1, 10000000 ! do something |
| end do |
| t2 = secnds (t1) ! elapsed time |
| print *, "Something took ", t2, " seconds." |
| end program test_secnds |
| @end smallexample |
| @end table |
| |
| |
| |
| @node SECOND |
| @section @code{SECOND} --- CPU time function |
| @fnindex SECOND |
| @cindex time, elapsed |
| @cindex elapsed time |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns a @code{REAL(4)} value representing the elapsed CPU time in |
| seconds. This provides the same functionality as the standard |
| @code{CPU_TIME} intrinsic, and is only included for backwards |
| compatibility. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL SECOND(TIME)} |
| @item @code{TIME = SECOND()} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{TIME} @tab Shall be of type @code{REAL(4)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| In either syntax, @var{TIME} is set to the process's current runtime in |
| seconds. |
| |
| @item @emph{See also}: |
| @ref{CPU_TIME} |
| |
| @end table |
| |
| |
| |
| @node SELECTED_INT_KIND |
| @section @code{SELECTED_INT_KIND} --- Choose integer kind |
| @fnindex SELECTED_INT_KIND |
| @cindex integer kind |
| @cindex kind, integer |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SELECTED_INT_KIND(I)} return the kind value of the smallest integer |
| type that can represent all values ranging from @math{-10^I} (exclusive) |
| to @math{10^I} (exclusive). If there is no integer kind that accommodates |
| this range, @code{SELECTED_INT_KIND} returns @math{-1}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SELECTED_INT_KIND(I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{I} @tab Shall be a scalar and of type @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| program large_integers |
| integer,parameter :: k5 = selected_int_kind(5) |
| integer,parameter :: k15 = selected_int_kind(15) |
| integer(kind=k5) :: i5 |
| integer(kind=k15) :: i15 |
| |
| print *, huge(i5), huge(i15) |
| |
| ! The following inequalities are always true |
| print *, huge(i5) >= 10_k5**5-1 |
| print *, huge(i15) >= 10_k15**15-1 |
| end program large_integers |
| @end smallexample |
| @end table |
| |
| |
| |
| @node SELECTED_REAL_KIND |
| @section @code{SELECTED_REAL_KIND} --- Choose real kind |
| @fnindex SELECTED_REAL_KIND |
| @cindex real kind |
| @cindex kind, real |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SELECTED_REAL_KIND(P,R)} return the kind value of a real data type |
| with decimal precision greater of at least @code{P} digits and exponent |
| range greater at least @code{R}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SELECTED_REAL_KIND(P, R)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{P} @tab (Optional) shall be a scalar and of type @code{INTEGER}. |
| @item @var{R} @tab (Optional) shall be a scalar and of type @code{INTEGER}. |
| @end multitable |
| At least one argument shall be present. |
| |
| @item @emph{Return value}: |
| |
| @code{SELECTED_REAL_KIND} returns the value of the kind type parameter of |
| a real data type with decimal precision of at least @code{P} digits and a |
| decimal exponent range of at least @code{R}. If more than one real data |
| type meet the criteria, the kind of the data type with the smallest |
| decimal precision is returned. If no real data type matches the criteria, |
| the result is |
| @table @asis |
| @item -1 if the processor does not support a real data type with a |
| precision greater than or equal to @code{P} |
| @item -2 if the processor does not support a real type with an exponent |
| range greater than or equal to @code{R} |
| @item -3 if neither is supported. |
| @end table |
| |
| @item @emph{Example}: |
| @smallexample |
| program real_kinds |
| integer,parameter :: p6 = selected_real_kind(6) |
| integer,parameter :: p10r100 = selected_real_kind(10,100) |
| integer,parameter :: r400 = selected_real_kind(r=400) |
| real(kind=p6) :: x |
| real(kind=p10r100) :: y |
| real(kind=r400) :: z |
| |
| print *, precision(x), range(x) |
| print *, precision(y), range(y) |
| print *, precision(z), range(z) |
| end program real_kinds |
| @end smallexample |
| @end table |
| |
| |
| |
| @node SET_EXPONENT |
| @section @code{SET_EXPONENT} --- Set the exponent of the model |
| @fnindex SET_EXPONENT |
| @cindex real number, set exponent |
| @cindex floating point, set exponent |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SET_EXPONENT(X, I)} returns the real number whose fractional part |
| is that that of @var{X} and whose exponent part is @var{I}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SET_EXPONENT(X, I)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @item @var{I} @tab Shall be of type @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as @var{X}. |
| The real number whose fractional part |
| is that that of @var{X} and whose exponent part if @var{I} is returned; |
| it is @code{FRACTION(X) * RADIX(X)**I}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_setexp |
| REAL :: x = 178.1387e-4 |
| INTEGER :: i = 17 |
| PRINT *, SET_EXPONENT(x, i), FRACTION(x) * RADIX(x)**i |
| END PROGRAM |
| @end smallexample |
| |
| @end table |
| |
| |
| |
| @node SHAPE |
| @section @code{SHAPE} --- Determine the shape of an array |
| @fnindex SHAPE |
| @cindex array, shape |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the shape of an array. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SHAPE(SOURCE)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SOURCE} @tab Shall be an array or scalar of any type. |
| If @var{SOURCE} is a pointer it must be associated and allocatable |
| arrays must be allocated. |
| @end multitable |
| |
| @item @emph{Return value}: |
| An @code{INTEGER} array of rank one with as many elements as @var{SOURCE} |
| has dimensions. The elements of the resulting array correspond to the extend |
| of @var{SOURCE} along the respective dimensions. If @var{SOURCE} is a scalar, |
| the result is the rank one array of size zero. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_shape |
| INTEGER, DIMENSION(-1:1, -1:2) :: A |
| WRITE(*,*) SHAPE(A) ! (/ 3, 4 /) |
| WRITE(*,*) SIZE(SHAPE(42)) ! (/ /) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{RESHAPE}, @ref{SIZE} |
| @end table |
| |
| |
| |
| @node SIGN |
| @section @code{SIGN} --- Sign copying function |
| @fnindex SIGN |
| @fnindex ISIGN |
| @fnindex DSIGN |
| @cindex sign copying |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SIGN(A,B)} returns the value of @var{A} with the sign of @var{B}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SIGN(A, B)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab Shall be of type @code{INTEGER} or @code{REAL} |
| @item @var{B} @tab Shall be of the same type and kind as @var{A} |
| @end multitable |
| |
| @item @emph{Return value}: |
| The kind of the return value is that of @var{A} and @var{B}. |
| If @math{B\ge 0} then the result is @code{ABS(A)}, else |
| it is @code{-ABS(A)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_sign |
| print *, sign(-12,1) |
| print *, sign(-12,0) |
| print *, sign(-12,-1) |
| |
| print *, sign(-12.,1.) |
| print *, sign(-12.,0.) |
| print *, sign(-12.,-1.) |
| end program test_sign |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Arguments @tab Return type @tab Standard |
| @item @code{ISIGN(A,P)} @tab @code{INTEGER(4)} @tab @code{INTEGER(4)} @tab f95, gnu |
| @item @code{DSIGN(A,P)} @tab @code{REAL(8)} @tab @code{REAL(8)} @tab f95, gnu |
| @end multitable |
| @end table |
| |
| |
| |
| @node SIGNAL |
| @section @code{SIGNAL} --- Signal handling subroutine (or function) |
| @fnindex SIGNAL |
| @cindex system, signal handling |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SIGNAL(NUMBER, HANDLER [, STATUS])} causes external subroutine |
| @var{HANDLER} to be executed with a single integer argument when signal |
| @var{NUMBER} occurs. If @var{HANDLER} is an integer, it can be used to |
| turn off handling of signal @var{NUMBER} or revert to its default |
| action. See @code{signal(2)}. |
| |
| If @code{SIGNAL} is called as a subroutine and the @var{STATUS} argument |
| is supplied, it is set to the value returned by @code{signal(2)}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL SIGNAL(NUMBER, HANDLER [, STATUS])} |
| @item @code{STATUS = SIGNAL(NUMBER, HANDLER)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{NUMBER} @tab Shall be a scalar integer, with @code{INTENT(IN)} |
| @item @var{HANDLER}@tab Signal handler (@code{INTEGER FUNCTION} or |
| @code{SUBROUTINE}) or dummy/global @code{INTEGER} scalar. |
| @code{INTEGER}. It is @code{INTENT(IN)}. |
| @item @var{STATUS} @tab (Optional) @var{STATUS} shall be a scalar |
| integer. It has @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The @code{SIGNAL} function returns the value returned by @code{signal(2)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_signal |
| intrinsic signal |
| external handler_print |
| |
| call signal (12, handler_print) |
| call signal (10, 1) |
| |
| call sleep (30) |
| end program test_signal |
| @end smallexample |
| @end table |
| |
| |
| |
| @node SIN |
| @section @code{SIN} --- Sine function |
| @fnindex SIN |
| @fnindex DSIN |
| @fnindex CSIN |
| @fnindex ZSIN |
| @fnindex CDSIN |
| @cindex trigonometric function, sine |
| @cindex sine |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SIN(X)} computes the sine of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SIN(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} or |
| @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value has same type and kind as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_sin |
| real :: x = 0.0 |
| x = sin(x) |
| end program test_sin |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DSIN(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab f95, gnu |
| @item @code{CSIN(X)} @tab @code{COMPLEX(4) X} @tab @code{COMPLEX(4)} @tab f95, gnu |
| @item @code{ZSIN(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab f95, gnu |
| @item @code{CDSIN(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab f95, gnu |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{ASIN} |
| @end table |
| |
| |
| |
| @node SINH |
| @section @code{SINH} --- Hyperbolic sine function |
| @fnindex SINH |
| @fnindex DSINH |
| @cindex hyperbolic sine |
| @cindex hyperbolic function, sine |
| @cindex sine, hyperbolic |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SINH(X)} computes the hyperbolic sine of @var{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SINH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_sinh |
| real(8) :: x = - 1.0_8 |
| x = sinh(x) |
| end program test_sinh |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DSINH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{ASINH} |
| @end table |
| |
| |
| |
| @node SIZE |
| @section @code{SIZE} --- Determine the size of an array |
| @fnindex SIZE |
| @cindex array, size |
| @cindex array, number of elements |
| @cindex array, count elements |
| |
| @table @asis |
| @item @emph{Description}: |
| Determine the extent of @var{ARRAY} along a specified dimension @var{DIM}, |
| or the total number of elements in @var{ARRAY} if @var{DIM} is absent. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SIZE(ARRAY[, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of any type. If @var{ARRAY} is |
| a pointer it must be associated and allocatable arrays must be allocated. |
| @item @var{DIM} @tab (Optional) shall be a scalar of type @code{INTEGER} |
| and its value shall be in the range from 1 to n, where n equals the rank |
| of @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default |
| integer kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_size |
| WRITE(*,*) SIZE((/ 1, 2 /)) ! 2 |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SHAPE}, @ref{RESHAPE} |
| @end table |
| |
| |
| |
| @node SLEEP |
| @section @code{SLEEP} --- Sleep for the specified number of seconds |
| @fnindex SLEEP |
| @cindex delayed execution |
| |
| @table @asis |
| @item @emph{Description}: |
| Calling this subroutine causes the process to pause for @var{SECONDS} seconds. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL SLEEP(SECONDS)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SECONDS} @tab The type shall be of default @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_sleep |
| call sleep(5) |
| end |
| @end smallexample |
| @end table |
| |
| |
| |
| @node SNGL |
| @section @code{SNGL} --- Convert double precision real to default real |
| @fnindex SNGL |
| @cindex conversion, to real |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SNGL(A)} converts the double precision real @var{A} |
| to a default real value. This is an archaic form of @code{REAL} |
| that is specific to one type for @var{A}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SNGL(A)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{A} @tab The type shall be a double precision @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type default @code{REAL}. |
| |
| @item @emph{See also}: |
| @ref{DBLE} |
| @end table |
| |
| |
| |
| @node SPACING |
| @section @code{SPACING} --- Smallest distance between two numbers of a given type |
| @fnindex SPACING |
| @cindex real number, relative spacing |
| @cindex floating point, relative spacing |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the distance between the argument @var{X} and the nearest |
| adjacent number of the same type. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SPACING(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is of the same type as the input argument @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_spacing |
| INTEGER, PARAMETER :: SGL = SELECTED_REAL_KIND(p=6, r=37) |
| INTEGER, PARAMETER :: DBL = SELECTED_REAL_KIND(p=13, r=200) |
| |
| WRITE(*,*) spacing(1.0_SGL) ! "1.1920929E-07" on i686 |
| WRITE(*,*) spacing(1.0_DBL) ! "2.220446049250313E-016" on i686 |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{RRSPACING} |
| @end table |
| |
| |
| |
| @node SPREAD |
| @section @code{SPREAD} --- Add a dimension to an array |
| @fnindex SPREAD |
| @cindex array, increase dimension |
| @cindex array, duplicate elementes |
| @cindex array, duplicate dimensions |
| |
| @table @asis |
| @item @emph{Description}: |
| Replicates a @var{SOURCE} array @var{NCOPIES} times along a specified |
| dimension @var{DIM}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SPREAD(SOURCE, DIM, NCOPIES)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SOURCE} @tab Shall be a scalar or an array of any type and |
| a rank less than seven. |
| @item @var{DIM} @tab Shall be a scalar of type @code{INTEGER} with a |
| value in the range from 1 to n+1, where n equals the rank of @var{SOURCE}. |
| @item @var{NCOPIES} @tab Shall be a scalar of type @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is an array of the same type as @var{SOURCE} and has rank n+1 |
| where n equals the rank of @var{SOURCE}. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_spread |
| INTEGER :: a = 1, b(2) = (/ 1, 2 /) |
| WRITE(*,*) SPREAD(A, 1, 2) ! "1 1" |
| WRITE(*,*) SPREAD(B, 1, 2) ! "1 1 2 2" |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{UNPACK} |
| @end table |
| |
| |
| |
| @node SQRT |
| @section @code{SQRT} --- Square-root function |
| @fnindex SQRT |
| @fnindex DSQRT |
| @fnindex CSQRT |
| @fnindex ZSQRT |
| @fnindex CDSQRT |
| @cindex root |
| @cindex square-root |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SQRT(X)} computes the square root of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SQRT(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)} or |
| @code{COMPLEX(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} or @code{COMPLEX(*)}. |
| The kind type parameter is the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_sqrt |
| real(8) :: x = 2.0_8 |
| complex :: z = (1.0, 2.0) |
| x = sqrt(x) |
| z = sqrt(z) |
| end program test_sqrt |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DSQRT(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F95 and later |
| @item @code{CSQRT(X)} @tab @code{COMPLEX(4) X} @tab @code{COMPLEX(4)} @tab F95 and later |
| @item @code{ZSQRT(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @item @code{CDSQRT(X)} @tab @code{COMPLEX(8) X} @tab @code{COMPLEX(8)} @tab GNU extension |
| @end multitable |
| @end table |
| |
| |
| |
| @node SRAND |
| @section @code{SRAND} --- Reinitialize the random number generator |
| @fnindex SRAND |
| @cindex random number generation, seeding |
| @cindex seeding a random number generator |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{SRAND} reinitializes the pseudo-random number generator |
| called by @code{RAND} and @code{IRAND}. The new seed used by the |
| generator is specified by the required argument @var{SEED}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL SRAND(SEED)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SEED} @tab Shall be a scalar @code{INTEGER(kind=4)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| Does not return. |
| |
| @item @emph{Example}: |
| See @code{RAND} and @code{IRAND} for examples. |
| |
| @item @emph{Notes}: |
| The Fortran 2003 standard specifies the intrinsic @code{RANDOM_SEED} to |
| initialize the pseudo-random numbers generator and @code{RANDOM_NUMBER} |
| to generate pseudo-random numbers. Please note that in |
| GNU Fortran, these two sets of intrinsics (@code{RAND}, |
| @code{IRAND} and @code{SRAND} on the one hand, @code{RANDOM_NUMBER} and |
| @code{RANDOM_SEED} on the other hand) access two independent |
| pseudo-random number generators. |
| |
| @item @emph{See also}: |
| @ref{RAND}, @ref{RANDOM_SEED}, @ref{RANDOM_NUMBER} |
| |
| @end table |
| |
| |
| |
| @node STAT |
| @section @code{STAT} --- Get file status |
| @fnindex STAT |
| @cindex file system, file status |
| |
| @table @asis |
| @item @emph{Description}: |
| This function returns information about a file. No permissions are required on |
| the file itself, but execute (search) permission is required on all of the |
| directories in path that lead to the file. |
| |
| The elements that are obtained and stored in the array @code{BUFF}: |
| @multitable @columnfractions .15 .70 |
| @item @code{buff(1)} @tab Device ID |
| @item @code{buff(2)} @tab Inode number |
| @item @code{buff(3)} @tab File mode |
| @item @code{buff(4)} @tab Number of links |
| @item @code{buff(5)} @tab Owner's uid |
| @item @code{buff(6)} @tab Owner's gid |
| @item @code{buff(7)} @tab ID of device containing directory entry for file (0 if not available) |
| @item @code{buff(8)} @tab File size (bytes) |
| @item @code{buff(9)} @tab Last access time |
| @item @code{buff(10)} @tab Last modification time |
| @item @code{buff(11)} @tab Last file status change time |
| @item @code{buff(12)} @tab Preferred I/O block size (-1 if not available) |
| @item @code{buff(13)} @tab Number of blocks allocated (-1 if not available) |
| @end multitable |
| |
| Not all these elements are relevant on all systems. |
| If an element is not relevant, it is returned as 0. |
| |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL STAT(FILE,BUFF[,STATUS])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{FILE} @tab The type shall be @code{CHARACTER(*)}, a valid path within the file system. |
| @item @var{BUFF} @tab The type shall be @code{INTEGER(4), DIMENSION(13)}. |
| @item @var{STATUS} @tab (Optional) status flag of type @code{INTEGER(4)}. Returns 0 |
| on success and a system specific error code otherwise. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_stat |
| INTEGER, DIMENSION(13) :: buff |
| INTEGER :: status |
| |
| CALL STAT("/etc/passwd", buff, status) |
| |
| IF (status == 0) THEN |
| WRITE (*, FMT="('Device ID:', T30, I19)") buff(1) |
| WRITE (*, FMT="('Inode number:', T30, I19)") buff(2) |
| WRITE (*, FMT="('File mode (octal):', T30, O19)") buff(3) |
| WRITE (*, FMT="('Number of links:', T30, I19)") buff(4) |
| WRITE (*, FMT="('Owner''s uid:', T30, I19)") buff(5) |
| WRITE (*, FMT="('Owner''s gid:', T30, I19)") buff(6) |
| WRITE (*, FMT="('Device where located:', T30, I19)") buff(7) |
| WRITE (*, FMT="('File size:', T30, I19)") buff(8) |
| WRITE (*, FMT="('Last access time:', T30, A19)") CTIME(buff(9)) |
| WRITE (*, FMT="('Last modification time', T30, A19)") CTIME(buff(10)) |
| WRITE (*, FMT="('Last status change time:', T30, A19)") CTIME(buff(11)) |
| WRITE (*, FMT="('Preferred block size:', T30, I19)") buff(12) |
| WRITE (*, FMT="('No. of blocks allocated:', T30, I19)") buff(13) |
| END IF |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| To stat an open file: @ref{FSTAT}, to stat a link: @ref{LSTAT} |
| @end table |
| |
| |
| |
| @node SUM |
| @section @code{SUM} --- Sum of array elements |
| @fnindex SUM |
| @cindex array, sum |
| @cindex array, add elements |
| @cindex array, conditionally add elements |
| @cindex sum array elements |
| |
| @table @asis |
| @item @emph{Description}: |
| Adds the elements of @var{ARRAY} along dimension @var{DIM} if |
| the corresponding element in @var{MASK} is @code{TRUE}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = SUM(ARRAY[, MASK])} |
| @code{RESULT = SUM(ARRAY, DIM[, MASK])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array of type @code{INTEGER(*)}, |
| @code{REAL(*)} or @code{COMPLEX(*)}. |
| @item @var{DIM} @tab (Optional) shall be a scalar of type |
| @code{INTEGER} with a value in the range from 1 to n, where n |
| equals the rank of @var{ARRAY}. |
| @item @var{MASK} @tab (Optional) shall be of type @code{LOGICAL} |
| and either be a scalar or an array of the same shape as @var{ARRAY}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result is of the same type as @var{ARRAY}. |
| |
| If @var{DIM} is absent, a scalar with the sum of all elements in @var{ARRAY} |
| is returned. Otherwise, an array of rank n-1, where n equals the rank of |
| @var{ARRAY},and a shape similar to that of @var{ARRAY} with dimension @var{DIM} |
| dropped is returned. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_sum |
| INTEGER :: x(5) = (/ 1, 2, 3, 4 ,5 /) |
| print *, SUM(x) ! all elements, sum = 15 |
| print *, SUM(x, MASK=MOD(x, 2)==1) ! odd elements, sum = 9 |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{PRODUCT} |
| @end table |
| |
| |
| |
| @node SYMLNK |
| @section @code{SYMLNK} --- Create a symbolic link |
| @fnindex SYMLNK |
| @cindex file system, create link |
| @cindex file system, soft link |
| |
| @table @asis |
| @item @emph{Description}: |
| Makes a symbolic link from file @var{PATH1} to @var{PATH2}. A null |
| character (@code{CHAR(0)}) can be used to mark the end of the names in |
| @var{PATH1} and @var{PATH2}; otherwise, trailing blanks in the file |
| names are ignored. If the @var{STATUS} argument is supplied, it |
| contains 0 on success or a nonzero error code upon return; see |
| @code{symlink(2)}. If the system does not supply @code{symlink(2)}, |
| @code{ENOSYS} is returned. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL SYMLNK(PATH1, PATH2 [, STATUS])} |
| @item @code{STATUS = SYMLNK(PATH1, PATH2)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PATH1} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{PATH2} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STATUS} @tab (Optional) Shall be of default @code{INTEGER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{LINK}, @ref{UNLINK} |
| |
| @end table |
| |
| |
| |
| @node SYSTEM |
| @section @code{SYSTEM} --- Execute a shell command |
| @fnindex SYSTEM |
| @cindex system, system call |
| |
| @table @asis |
| @item @emph{Description}: |
| Passes the command @var{COMMAND} to a shell (see @code{system(3)}). If |
| argument @var{STATUS} is present, it contains the value returned by |
| @code{system(3)}, which is presumably 0 if the shell command succeeded. |
| Note that which shell is used to invoke the command is system-dependent |
| and environment-dependent. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL SYSTEM(COMMAND [, STATUS])} |
| @item @code{STATUS = SYSTEM(COMMAND)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{COMMAND} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STATUS} @tab (Optional) Shall be of default @code{INTEGER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @end table |
| |
| |
| |
| @node SYSTEM_CLOCK |
| @section @code{SYSTEM_CLOCK} --- Time function |
| @fnindex SYSTEM_CLOCK |
| @cindex time, clock ticks |
| @cindex clock ticks |
| |
| @table @asis |
| @item @emph{Description}: |
| Determines the @var{COUNT} of milliseconds of wall clock time since |
| the Epoch (00:00:00 UTC, January 1, 1970) modulo @var{COUNT_MAX}, |
| @var{COUNT_RATE} determines the number of clock ticks per second. |
| @var{COUNT_RATE} and @var{COUNT_MAX} are constant and specific to |
| @command{gfortran}. |
| |
| If there is no clock, @var{COUNT} is set to @code{-HUGE(COUNT)}, and |
| @var{COUNT_RATE} and @var{COUNT_MAX} are set to zero |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL SYSTEM_CLOCK([COUNT, COUNT_RATE, COUNT_MAX])} |
| |
| @item @emph{Arguments}: |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{COUNT} @tab (Optional) shall be a scalar of type default |
| @code{INTEGER} with @code{INTENT(OUT)}. |
| @item @var{COUNT_RATE} @tab (Optional) shall be a scalar of type default |
| @code{INTEGER} with @code{INTENT(OUT)}. |
| @item @var{COUNT_MAX} @tab (Optional) shall be a scalar of type default |
| @code{INTEGER} with @code{INTENT(OUT)}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_system_clock |
| INTEGER :: count, count_rate, count_max |
| CALL SYSTEM_CLOCK(count, count_rate, count_max) |
| WRITE(*,*) count, count_rate, count_max |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{DATE_AND_TIME}, @ref{CPU_TIME} |
| @end table |
| |
| |
| |
| @node TAN |
| @section @code{TAN} --- Tangent function |
| @fnindex TAN |
| @fnindex DTAN |
| @cindex trigonometric function, tangent |
| @cindex tangent |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{TAN(X)} computes the tangent of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TAN(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)}. The kind type parameter is |
| the same as @var{X}. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_tan |
| real(8) :: x = 0.165_8 |
| x = tan(x) |
| end program test_tan |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DTAN(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{ATAN} |
| @end table |
| |
| |
| |
| @node TANH |
| @section @code{TANH} --- Hyperbolic tangent function |
| @fnindex TANH |
| @fnindex DTANH |
| @cindex hyperbolic tangent |
| @cindex hyperbolic function, tangent |
| @cindex tangent, hyperbolic |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{TANH(X)} computes the hyperbolic tangent of @var{X}. |
| |
| @item @emph{Standard}: |
| F77 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{X = TANH(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be @code{REAL(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{REAL(*)} and lies in the range |
| @math{ - 1 \leq tanh(x) \leq 1 }. |
| |
| @item @emph{Example}: |
| @smallexample |
| program test_tanh |
| real(8) :: x = 2.1_8 |
| x = tanh(x) |
| end program test_tanh |
| @end smallexample |
| |
| @item @emph{Specific names}: |
| @multitable @columnfractions .20 .20 .20 .25 |
| @item Name @tab Argument @tab Return type @tab Standard |
| @item @code{DTANH(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)} @tab F95 and later |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{ATANH} |
| @end table |
| |
| |
| |
| @node TIME |
| @section @code{TIME} --- Time function |
| @fnindex TIME |
| @cindex time, current |
| @cindex current time |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the current time encoded as an integer (in the manner of the |
| UNIX function @code{time(3)}). This value is suitable for passing to |
| @code{CTIME()}, @code{GMTIME()}, and @code{LTIME()}. |
| |
| This intrinsic is not fully portable, such as to systems with 32-bit |
| @code{INTEGER} types but supporting times wider than 32 bits. Therefore, |
| the values returned by this intrinsic might be, or become, negative, or |
| numerically less than previous values, during a single run of the |
| compiled program. |
| |
| See @ref{TIME8}, for information on a similar intrinsic that might be |
| portable to more GNU Fortran implementations, though to fewer Fortran |
| compilers. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TIME()} |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER(4)}. |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{GMTIME}, @ref{LTIME}, @ref{MCLOCK}, @ref{TIME8} |
| |
| @end table |
| |
| |
| |
| @node TIME8 |
| @section @code{TIME8} --- Time function (64-bit) |
| @fnindex TIME8 |
| @cindex time, current |
| @cindex current time |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the current time encoded as an integer (in the manner of the |
| UNIX function @code{time(3)}). This value is suitable for passing to |
| @code{CTIME()}, @code{GMTIME()}, and @code{LTIME()}. |
| |
| @emph{Warning:} this intrinsic does not increase the range of the timing |
| values over that returned by @code{time(3)}. On a system with a 32-bit |
| @code{time(3)}, @code{TIME8()} will return a 32-bit value, even though |
| it is converted to a 64-bit @code{INTEGER(8)} value. That means |
| overflows of the 32-bit value can still occur. Therefore, the values |
| returned by this intrinsic might be or become negative or numerically |
| less than previous values during a single run of the compiled program. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TIME8()} |
| |
| @item @emph{Return value}: |
| The return value is a scalar of type @code{INTEGER(8)}. |
| |
| @item @emph{See also}: |
| @ref{CTIME}, @ref{GMTIME}, @ref{LTIME}, @ref{MCLOCK8}, @ref{TIME} |
| |
| @end table |
| |
| |
| |
| @node TINY |
| @section @code{TINY} --- Smallest positive number of a real kind |
| @fnindex TINY |
| @cindex limits, smallest number |
| @cindex model representation, smallest number |
| |
| @table @asis |
| @item @emph{Description}: |
| @code{TINY(X)} returns the smallest positive (non zero) number |
| in the model of the type of @code{X}. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TINY(X)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab Shall be of type @code{REAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of the same type and kind as @var{X} |
| |
| @item @emph{Example}: |
| See @code{HUGE} for an example. |
| @end table |
| |
| |
| |
| @node TRANSFER |
| @section @code{TRANSFER} --- Transfer bit patterns |
| @fnindex TRANSFER |
| @cindex bits, move |
| @cindex type cast |
| |
| @table @asis |
| @item @emph{Description}: |
| Interprets the bitwise representation of @var{SOURCE} in memory as if it |
| is the representation of a variable or array of the same type and type |
| parameters as @var{MOLD}. |
| |
| This is approximately equivalent to the C concept of @emph{casting} one |
| type to another. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TRANSFER(SOURCE, MOLD[, SIZE])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{SOURCE} @tab Shall be a scalar or an array of any type. |
| @item @var{MOLD} @tab Shall be a scalar or an array of any type. |
| @item @var{SIZE} @tab (Optional) shall be a scalar of type |
| @code{INTEGER}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result has the same type as @var{MOLD}, with the bit level |
| representation of @var{SOURCE}. If @var{SIZE} is present, the result is |
| a one-dimensional array of length @var{SIZE}. If @var{SIZE} is absent |
| but @var{MOLD} is an array (of any size or shape), the result is a one- |
| dimensional array of the minimum length needed to contain the entirety |
| of the bitwise representation of @var{SOURCE}. If @var{SIZE} is absent |
| and @var{MOLD} is a scalar, the result is a scalar. |
| |
| If the bitwise representation of the result is longer than that of |
| @var{SOURCE}, then the leading bits of the result correspond to those of |
| @var{SOURCE} and any trailing bits are filled arbitrarily. |
| |
| When the resulting bit representation does not correspond to a valid |
| representation of a variable of the same type as @var{MOLD}, the results |
| are undefined, and subsequent operations on the result cannot be |
| guaranteed to produce sensible behavior. For example, it is possible to |
| create @code{LOGICAL} variables for which @code{@var{VAR}} and |
| @code{.NOT.@var{VAR}} both appear to be true. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_transfer |
| integer :: x = 2143289344 |
| print *, transfer(x, 1.0) ! prints "NaN" on i686 |
| END PROGRAM |
| @end smallexample |
| @end table |
| |
| |
| |
| @node TRANSPOSE |
| @section @code{TRANSPOSE} --- Transpose an array of rank two |
| @fnindex TRANSPOSE |
| @cindex array, transpose |
| @cindex matrix, transpose |
| @cindex transpose |
| |
| @table @asis |
| @item @emph{Description}: |
| Transpose an array of rank two. Element (i, j) of the result has the value |
| @code{MATRIX(j, i)}, for all i, j. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TRANSPOSE(MATRIX)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MATRIX} @tab Shall be an array of any type and have a rank of two. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The result has the the same type as @var{MATRIX}, and has shape |
| @code{(/ m, n /)} if @var{MATRIX} has shape @code{(/ n, m /)}. |
| @end table |
| |
| |
| |
| @node TRIM |
| @section @code{TRIM} --- Remove trailing blank characters of a string |
| @fnindex TRIM |
| @cindex string, remove trailing whitespace |
| |
| @table @asis |
| @item @emph{Description}: |
| Removes trailing blank characters of a string. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = TRIM(STRING)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be a scalar of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| A scalar of type @code{CHARACTER(*)} which length is that of @var{STRING} |
| less the number of trailing blanks. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_trim |
| CHARACTER(len=10), PARAMETER :: s = "GFORTRAN " |
| WRITE(*,*) LEN(s), LEN(TRIM(s)) ! "10 8", with/without trailing blanks |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ADJUSTL}, @ref{ADJUSTR} |
| @end table |
| |
| |
| |
| @node TTYNAM |
| @section @code{TTYNAM} --- Get the name of a terminal device. |
| @fnindex TTYNAM |
| @cindex system, terminal |
| |
| @table @asis |
| @item @emph{Description}: |
| Get the name of a terminal device. For more information, |
| see @code{ttyname(3)}. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL TTYNAM(UNIT, NAME)} |
| @item @code{NAME = TTYNAM(UNIT)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{UNIT} @tab Shall be a scalar @code{INTEGER(*)}. |
| @item @var{NAME} @tab Shall be of type @code{CHARACTER(*)}. |
| @end multitable |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_ttynam |
| INTEGER :: unit |
| DO unit = 1, 10 |
| IF (isatty(unit=unit)) write(*,*) ttynam(unit) |
| END DO |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{ISATTY} |
| @end table |
| |
| |
| |
| @node UBOUND |
| @section @code{UBOUND} --- Upper dimension bounds of an array |
| @fnindex UBOUND |
| @cindex array, upper bound |
| |
| @table @asis |
| @item @emph{Description}: |
| Returns the upper bounds of an array, or a single upper bound |
| along the @var{DIM} dimension. |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Inquiry function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = UBOUND(ARRAY [, DIM])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{ARRAY} @tab Shall be an array, of any type. |
| @item @var{DIM} @tab (Optional) Shall be a scalar @code{INTEGER(*)}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| If @var{DIM} is absent, the result is an array of the upper bounds of |
| @var{ARRAY}. If @var{DIM} is present, the result is a scalar |
| corresponding to the upper bound of the array along that dimension. If |
| @var{ARRAY} is an expression rather than a whole array or array |
| structure component, or if it has a zero extent along the relevant |
| dimension, the upper bound is taken to be the number of elements along |
| the relevant dimension. |
| |
| @item @emph{See also}: |
| @ref{LBOUND} |
| @end table |
| |
| |
| |
| @node UMASK |
| @section @code{UMASK} --- Set the file creation mask |
| @fnindex UMASK |
| @cindex file system, file creation mask |
| |
| @table @asis |
| @item @emph{Description}: |
| Sets the file creation mask to @var{MASK} and returns the old value in |
| argument @var{OLD} if it is supplied. See @code{umask(2)}. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine |
| |
| @item @emph{Syntax}: |
| @code{CALL UMASK(MASK [, OLD])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{MASK} @tab Shall be a scalar of type @code{INTEGER(*)}. |
| @item @var{MASK} @tab (Optional) Shall be a scalar of type |
| @code{INTEGER(*)}. |
| @end multitable |
| |
| @end table |
| |
| |
| |
| @node UNLINK |
| @section @code{UNLINK} --- Remove a file from the file system |
| @fnindex UNLINK |
| @cindex file system, remove file |
| |
| @table @asis |
| @item @emph{Description}: |
| Unlinks the file @var{PATH}. A null character (@code{CHAR(0)}) can be |
| used to mark the end of the name in @var{PATH}; otherwise, trailing |
| blanks in the file name are ignored. If the @var{STATUS} argument is |
| supplied, it contains 0 on success or a nonzero error code upon return; |
| see @code{unlink(2)}. |
| |
| This intrinsic is provided in both subroutine and function forms; |
| however, only one form can be used in any given program unit. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Subroutine, non-elemental function |
| |
| @item @emph{Syntax}: |
| @multitable @columnfractions .80 |
| @item @code{CALL UNLINK(PATH [, STATUS])} |
| @item @code{STATUS = UNLINK(PATH)} |
| @end multitable |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{PATH} @tab Shall be of default @code{CHARACTER} type. |
| @item @var{STATUS} @tab (Optional) Shall be of default @code{INTEGER} type. |
| @end multitable |
| |
| @item @emph{See also}: |
| @ref{LINK}, @ref{SYMLNK} |
| @end table |
| |
| |
| |
| @node UNPACK |
| @section @code{UNPACK} --- Unpack an array of rank one into an array |
| @fnindex UNPACK |
| @cindex array, unpacking |
| @cindex array, increase dimension |
| @cindex array, scatter elements |
| |
| @table @asis |
| @item @emph{Description}: |
| Store the elements of @var{VECTOR} in an array of higher rank. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Transformational function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = UNPACK(VECTOR, MASK, FIELD)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{VECTOR} @tab Shall be an array of any type and rank one. It |
| shall have at least as many elements as @var{MASK} has @code{TRUE} values. |
| @item @var{MASK} @tab Shall be an array of type @code{LOGICAL}. |
| @item @var{FIELD} @tab Shall be of the sam type as @var{VECTOR} and have |
| the same shape as @var{MASK}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The resulting array corresponds to @var{FIELD} with @code{TRUE} elements |
| of @var{MASK} replaced by values from @var{VECTOR} in array element order. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_unpack |
| integer :: vector(2) = (/1,1/) |
| logical :: mask(4) = (/ .TRUE., .FALSE., .FALSE., .TRUE. /) |
| integer :: field(2,2) = 0, unity(2,2) |
| |
| ! result: unity matrix |
| unity = unpack(vector, reshape(mask, (/2,2/)), field) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{PACK}, @ref{SPREAD} |
| @end table |
| |
| |
| |
| @node VERIFY |
| @section @code{VERIFY} --- Scan a string for the absence of a set of characters |
| @fnindex VERIFY |
| @cindex string, find missing set |
| |
| @table @asis |
| @item @emph{Description}: |
| Verifies that all the characters in a @var{SET} are present in a @var{STRING}. |
| |
| If @var{BACK} is either absent or equals @code{FALSE}, this function |
| returns the position of the leftmost character of @var{STRING} that is |
| not in @var{SET}. If @var{BACK} equals @code{TRUE}, the rightmost position |
| is returned. If all characters of @var{SET} are found in @var{STRING}, the |
| result is zero. |
| |
| @item @emph{Standard}: |
| F95 and later |
| |
| @item @emph{Class}: |
| Elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = VERFIY(STRING, SET[, BACK])} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{STRING} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{SET} @tab Shall be of type @code{CHARACTER(*)}. |
| @item @var{BACK} @tab (Optional) shall be of type @code{LOGICAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return value is of type @code{INTEGER} and of the default |
| integer kind. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_verify |
| WRITE(*,*) VERIFY("FORTRAN", "AO") ! 1, found 'F' |
| WRITE(*,*) VERIFY("FORTRAN", "FOO") ! 3, found 'R' |
| WRITE(*,*) VERIFY("FORTRAN", "C++") ! 1, found 'F' |
| WRITE(*,*) VERIFY("FORTRAN", "C++", .TRUE.) ! 7, found 'N' |
| WRITE(*,*) VERIFY("FORTRAN", "FORTRAN") ! 0' found none |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| @ref{SCAN}, @ref{INDEX} |
| @end table |
| |
| |
| |
| @node XOR |
| @section @code{XOR} --- Bitwise logical exclusive OR |
| @fnindex XOR |
| @cindex bitwise logical exclusive or |
| @cindex logical exclusive or, bitwise |
| |
| @table @asis |
| @item @emph{Description}: |
| Bitwise logical exclusive or. |
| |
| This intrinsic routine is provided for backwards compatibility with |
| GNU Fortran 77. For integer arguments, programmers should consider |
| the use of the @ref{IEOR} intrinsic defined by the Fortran standard. |
| |
| @item @emph{Standard}: |
| GNU extension |
| |
| @item @emph{Class}: |
| Non-elemental function |
| |
| @item @emph{Syntax}: |
| @code{RESULT = XOR(X, Y)} |
| |
| @item @emph{Arguments}: |
| @multitable @columnfractions .15 .70 |
| @item @var{X} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @item @var{Y} @tab The type shall be either @code{INTEGER(*)} or @code{LOGICAL}. |
| @end multitable |
| |
| @item @emph{Return value}: |
| The return type is either @code{INTEGER(*)} or @code{LOGICAL} |
| after cross-promotion of the arguments. |
| |
| @item @emph{Example}: |
| @smallexample |
| PROGRAM test_xor |
| LOGICAL :: T = .TRUE., F = .FALSE. |
| INTEGER :: a, b |
| DATA a / Z'F' /, b / Z'3' / |
| |
| WRITE (*,*) XOR(T, T), XOR(T, F), XOR(F, T), XOR(F, F) |
| WRITE (*,*) XOR(a, b) |
| END PROGRAM |
| @end smallexample |
| |
| @item @emph{See also}: |
| F95 elemental function: @ref{IEOR} |
| @end table |
| |
| |