libquadmath/math/cprojq.c

   1 /* Compute projection of complex float type value to Riemann sphere.
   2    Copyright (C) 1997-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include "quadmath-imp.h"
  21
  22 __complex128
  23 cprojq (__complex128 x)
  24 {
  25   if (isinfq (__real__ x) || isinfq (__imag__ x))
  26     {
  27       __complex128 res;
  28
  29       __real__ res = __builtin_inf ();
  30       __imag__ res = copysignq (0, __imag__ x);
  31
  32       return res;
  33     }
  34
  35   return x;
  36 }