| 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 | #include "math_private.h" |
|---|
| 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 |
|---|
