gcc/fortran/doc/gfortran/intrinsic-procedures/asin.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 .. _asin:
   7
   8 .. index:: ASIN
   9
  10 .. index:: DASIN
  11
  12 .. index:: trigonometric function, sine, inverse
  13
  14 .. index:: sine, inverse
  15
  16 ASIN --- Arcsine function
  17 **************************
  18
  19 .. function:: ASIN(X)
  20
  21   ``ASIN(X)`` computes the arcsine of its :samp:`{X}` (inverse of ``SIN(X)``).
  22
  23   :param X:
  24     The type shall be either ``REAL`` and a magnitude that is
  25     less than or equal to one - or be ``COMPLEX``.
  26
  27   :return:
  28     The return value is of the same type and kind as :samp:`{X}`.
  29     The real part of the result is in radians and lies in the range
  30     -\pi/2 \leq \Re \asin(x) \leq \pi/2.
  31
  32   Standard:
  33     Fortran 77 and later, for a complex argument Fortran 2008 or later
  34
  35   Class:
  36     Elemental function
  37
  38   Syntax:
  39     .. code-block:: fortran
  40
  41       RESULT = ASIN(X)
  42
  43   Example:
  44     .. code-block:: fortran
  45
  46       program test_asin
  47         real(8) :: x = 0.866_8
  48         x = asin(x)
  49       end program test_asin
  50
  51   Specific names:
  52     .. list-table::
  53        :header-rows: 1
  54
  55        * - Name
  56          - Argument
  57          - Return type
  58          - Standard
  59
  60        * - ``ASIN(X)``
  61          - ``REAL(4) X``
  62          - ``REAL(4)``
  63          - Fortran 77 and later
  64        * - ``DASIN(X)``
  65          - ``REAL(8) X``
  66          - ``REAL(8)``
  67          - Fortran 77 and later
  68
  69   See also:
  70     Inverse function:
  71     :ref:`SIN`
  72     Degrees function:
  73     :ref:`ASIND`