gcc/fortran/doc/gfortran/intrinsic-procedures/reshape.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 .. index:: RESHAPE, array, change dimensions, array, transmogrify
   7
   8 .. _reshape:
   9
  10 RESHAPE --- Function to reshape an array
  11 ****************************************
  12
  13 .. function:: RESHAPE(SOURCE, SHAPE, PAD, ORDER)
  14
  15   Reshapes :samp:`{SOURCE}` to correspond to :samp:`{SHAPE}`. If necessary,
  16   the new array may be padded with elements from :samp:`{PAD}` or permuted
  17   as defined by :samp:`{ORDER}`.
  18
  19   :param SOURCE:
  20     Shall be an array of any type.
  21
  22   :param SHAPE:
  23     Shall be of type ``INTEGER`` and an
  24     array of rank one. Its values must be positive or zero.
  25
  26   :param PAD:
  27     (Optional) shall be an array of the same
  28     type as :samp:`{SOURCE}`.
  29
  30   :param ORDER:
  31     (Optional) shall be of type ``INTEGER``
  32     and an array of the same shape as :samp:`{SHAPE}`. Its values shall
  33     be a permutation of the numbers from 1 to n, where n is the size of
  34     :samp:`{SHAPE}`. If :samp:`{ORDER}` is absent, the natural ordering shall
  35     be assumed.
  36
  37   :return:
  38     The result is an array of shape :samp:`{SHAPE}` with the same type as
  39     :samp:`{SOURCE}`.
  40
  41   Standard:
  42     Fortran 90 and later
  43
  44   Class:
  45     Transformational function
  46
  47   Syntax:
  48     .. code-block:: fortran
  49
  50       RESULT = RESHAPE(SOURCE, SHAPE[, PAD, ORDER])
  51
  52   Example:
  53     .. code-block:: fortran
  54
  55       PROGRAM test_reshape
  56         INTEGER, DIMENSION(4) :: x
  57         WRITE(*,*) SHAPE(x)                       ! prints "4"
  58         WRITE(*,*) SHAPE(RESHAPE(x, (/2, 2/)))    ! prints "2 2"
  59       END PROGRAM
  60
  61   See also:
  62     :ref:`SHAPE`