1 /* Return cosine of complex double value. 2 Copyright (C) 1997 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 <fenv.h> 23 #include <math.h> 24 25 26 __complex__ double 27 __ccos (__complex__ double x) 28 { 29 __complex__ double res; 30 31 if (!isfinite (__real__ x) || __isnan (__imag__ x)) 32 { 33 if (__real__ x == 0.0 || __imag__ x == 0.0) 34 { 35 __real__ res = __nan (""); 36 __imag__ res = 0.0; 37 38 #ifdef FE_INVALID 39 if (__isinf (__real__ x)) 40 feraiseexcept (FE_INVALID); 41 #endif 42 } 43 else if (__isinf (__imag__ x)) 44 { 45 __real__ res = HUGE_VAL; 46 __imag__ res = __nan (""); 47 48 #ifdef FE_INVALID 49 if (__isinf (__real__ x)) 50 feraiseexcept (FE_INVALID); 51 #endif 52 } 53 else 54 { 55 __real__ res = __nan (""); 56 __imag__ res = __nan (""); 57 58 #ifdef FE_INVALID 59 if (isfinite (__imag__ x)) 60 feraiseexcept (FE_INVALID); 61 #endif 62 } 63 } 64 else 65 { 66 __complex__ double y; 67 68 __real__ y = -__imag__ x; 69 __imag__ y = __real__ x; 70 71 res = __ccosh (y); 72 } 73 74 return res; 75 } 76 weak_alias (__ccos, ccos) 77 #ifdef NO_LONG_DOUBLE 78 strong_alias (__ccos, __ccosl) 79 weak_alias (__ccos, ccosl) 80 #endif 81