| /* Return cosine of complex double value. |
| Copyright (C) 1997-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <complex.h> |
| #include <math.h> |
| |
| __complex__ double |
| __cacos (__complex__ double x) |
| { |
| __complex__ double y; |
| __complex__ double res; |
| int rcls = fpclassify (__real__ x); |
| int icls = fpclassify (__imag__ x); |
| |
| if (rcls <= FP_INFINITE || icls <= FP_INFINITE |
| || (rcls == FP_ZERO && icls == FP_ZERO)) |
| { |
| y = __casin (x); |
| |
| __real__ res = (double) M_PI_2 - __real__ y; |
| __imag__ res = -__imag__ y; |
| } |
| else |
| { |
| __real__ y = -__imag__ x; |
| __imag__ y = __real__ x; |
| |
| y = __kernel_casinh (y, 1); |
| |
| __real__ res = __imag__ y; |
| __imag__ res = __real__ y; |
| } |
| |
| return res; |
| } |
| weak_alias (__cacos, cacos) |
| #ifdef NO_LONG_DOUBLE |
| strong_alias (__cacos, __cacosl) |
| weak_alias (__cacos, cacosl) |
| #endif |
