gcc/fortran/doc/gfortran/intrinsic-procedures/sign.rst

   1 ..
   2   Copyright 1988-2022 Free Software Foundation, Inc.
   3   This is part of the GCC manual.
   4   For copying conditions, see the copyright.rst file.
   5
   6 .. _sign:
   7
   8 .. index:: SIGN
   9
  10 .. index:: ISIGN
  11
  12 .. index:: DSIGN
  13
  14 .. index:: sign copying
  15
  16 SIGN --- Sign copying function
  17 ******************************
  18
  19 .. function:: SIGN(A,B)
  20
  21   ``SIGN(A,B)`` returns the value of :samp:`{A}` with the sign of :samp:`{B}`.
  22
  23   :param A:
  24     Shall be of type ``INTEGER`` or ``REAL``
  25
  26   :param B:
  27     Shall be of the same type and kind as :samp:`{A}`.
  28
  29   :return:
  30     The kind of the return value is that of :samp:`{A}` and :samp:`{B}`.
  31     If B \ge 0 then the result is ``ABS(A)``, else
  32     it is ``-ABS(A)``.
  33
  34   Standard:
  35     Fortran 77 and later
  36
  37   Class:
  38     Elemental function
  39
  40   Syntax:
  41     .. code-block:: fortran
  42
  43       RESULT = SIGN(A, B)
  44
  45   Example:
  46     .. code-block:: fortran
  47
  48       program test_sign
  49         print *, sign(-12,1)
  50         print *, sign(-12,0)
  51         print *, sign(-12,-1)
  52
  53         print *, sign(-12.,1.)
  54         print *, sign(-12.,0.)
  55         print *, sign(-12.,-1.)
  56       end program test_sign
  57
  58   Specific names:
  59     .. list-table::
  60        :header-rows: 1
  61
  62        * - Name
  63          - Arguments
  64          - Return type
  65          - Standard
  66
  67        * - ``SIGN(A,B)``
  68          - ``REAL(4) A, B``
  69          - ``REAL(4)``
  70          - Fortran 77 and later
  71        * - ``ISIGN(A,B)``
  72          - ``INTEGER(4) A, B``
  73          - ``INTEGER(4)``
  74          - Fortran 77 and later
  75        * - ``DSIGN(A,B)``
  76          - ``REAL(8) A, B``
  77          - ``REAL(8)``
  78          - Fortran 77 and later