g77.info: Table of Intrinsic Functions

Table of Intrinsic Functions

   (Corresponds to Section 15.10 of ANSI X3.9-1978 FORTRAN 77.)

   The GNU Fortran language adds various functions, subroutines, types,
and arguments to the set of intrinsic functions in ANSI FORTRAN 77.
The complete set of intrinsics supported by the GNU Fortran language is
described below.

   Note that a name is not treated as that of an intrinsic if it is
specified in an `EXTERNAL' statement in the same program unit; if a
command-line option is used to disable the groups to which the
intrinsic belongs; or if the intrinsic is not named in an `INTRINSIC'
statement and a command-line option is used to hide the groups to which
the intrinsic belongs.

   So, it is recommended that any reference in a program unit to an
intrinsic procedure that is not a standard FORTRAN 77 intrinsic be
accompanied by an appropriate `INTRINSIC' statement in that program
unit.  This sort of defensive programming makes it more likely that an
implementation will issue a diagnostic rather than generate incorrect
code for such a reference.

   The terminology used below is based on that of the Fortran 90
standard, so that the text may be more concise and accurate:

   * `OPTIONAL' means the argument may be omitted.

   * `A-1, A-2, ..., A-n' means more than one argument (generally named
     `A') may be specified.

   * `scalar' means the argument must not be an array (must be a
     variable or array element, or perhaps a constant if expressions
     are permitted).

   * `DIMENSION(4)' means the argument must be an array having 4
     elements.

   * `INTENT(IN)' means the argument must be an expression (such as a
     constant or a variable that is defined upon invocation of the
     intrinsic).

   * `INTENT(OUT)' means the argument must be definable by the
     invocation of the intrinsic (that is, must not be a constant nor
     an expression involving operators other than array reference and
     substring reference).

   * `INTENT(INOUT)' means the argument must be defined prior to, and
     definable by, invocation of the intrinsic (a combination of the
     requirements of `INTENT(IN)' and `INTENT(OUT)'.

   * *Note Kind Notation::, for an explanation of `KIND'.

   (Note that the empty lines appearing in the menu below are not
intentional--they result from a bug in the GNU `makeinfo' program...a
program that, if it did not exist, would leave this document in far
worse shape!)

Menu