1: /* Return cosine of complex long double value.
    2:    Copyright (C) 1997, 1998 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, write to the Free
   18:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   19:    02111-1307 USA.  */
   20: 
   21: #include <complex.h>
   22: #include <math.h>
   23: 
   24: __complex__ long double
   25: __cacosl (__complex__ long double x)
   26: {
   27:   __complex__ long double y;
   28:   __complex__ long double res;
   29: 
   30:   y = __casinl (x);
   31: 
   32:   __real__ res = M_PI_2l - __real__ y;
   33:   __imag__ res = -__imag__ y;
   34: 
   35:   return res;
   36: }
   37: weak_alias (__cacosl, cacosl)