Fix __getcwd rewinddir namespace (bug 17584).
[glibc.git] / math / s_cacos.c
blob2c22817d4d076786c74bf5ce163bc916ef6801e9
1 /* Return cosine of complex double value.
2 Copyright (C) 1997-2014 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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.
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.
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/>. */
20 #include <complex.h>
21 #include <math.h>
23 __complex__ double
24 __cacos (__complex__ double x)
26 __complex__ double y;
27 __complex__ double res;
28 int rcls = fpclassify (__real__ x);
29 int icls = fpclassify (__imag__ x);
31 if (rcls <= FP_INFINITE || icls <= FP_INFINITE
32 || (rcls == FP_ZERO && icls == FP_ZERO))
34 y = __casin (x);
36 __real__ res = (double) M_PI_2 - __real__ y;
37 if (__real__ res == 0.0)
38 __real__ res = 0.0;
39 __imag__ res = -__imag__ y;
41 else
43 __real__ y = -__imag__ x;
44 __imag__ y = __real__ x;
46 y = __kernel_casinh (y, 1);
48 __real__ res = __imag__ y;
49 __imag__ res = __real__ y;
52 return res;
54 weak_alias (__cacos, cacos)
55 #ifdef NO_LONG_DOUBLE
56 strong_alias (__cacos, __cacosl)
57 weak_alias (__cacos, cacosl)
58 #endif