| 1 | /* Return arc hyperbole cosine for 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 | #include "math_private.h" |
|---|
| 24 | |
|---|
| 25 | __complex__ long double |
|---|
| 26 | __cacoshl (__complex__ long double x) |
|---|
| 27 | { |
|---|
| 28 | __complex__ long double res; |
|---|
| 29 | int rcls = fpclassify (__real__ x); |
|---|
| 30 | int icls = fpclassify (__imag__ x); |
|---|
| 31 | |
|---|
| 32 | if (rcls <= FP_INFINITE || icls <= FP_INFINITE) |
|---|
| 33 | { |
|---|
| 34 | if (icls == FP_INFINITE) |
|---|
| 35 | { |
|---|
| 36 | __real__ res = HUGE_VALL; |
|---|
| 37 | |
|---|
| 38 | if (rcls == FP_NAN) |
|---|
| 39 | __imag__ res = __nanl (""); |
|---|
| 40 | else |
|---|
| 41 | __imag__ res = __copysignl ((rcls == FP_INFINITE |
|---|
| 42 | ? (__real__ x < 0.0 |
|---|
| 43 | ? M_PIl - M_PI_4l : M_PI_4l) |
|---|
| 44 | : M_PI_2l), __imag__ x); |
|---|
| 45 | } |
|---|
| 46 | else if (rcls == FP_INFINITE) |
|---|
| 47 | { |
|---|
| 48 | __real__ res = HUGE_VALL; |
|---|
| 49 | |
|---|
| 50 | if (icls >= FP_ZERO) |
|---|
| 51 | __imag__ res = __copysignl (signbit (__real__ x) ? M_PIl : 0.0, |
|---|
| 52 | __imag__ x); |
|---|
| 53 | else |
|---|
| 54 | __imag__ res = __nanl (""); |
|---|
| 55 | } |
|---|
| 56 | else |
|---|
| 57 | { |
|---|
| 58 | __real__ res = __nanl (""); |
|---|
| 59 | __imag__ res = __nanl (""); |
|---|
| 60 | } |
|---|
| 61 | } |
|---|
| 62 | else if (rcls == FP_ZERO && icls == FP_ZERO) |
|---|
| 63 | { |
|---|
| 64 | __real__ res = 0.0; |
|---|
| 65 | __imag__ res = __copysignl (M_PI_2l, __imag__ x); |
|---|
| 66 | } |
|---|
| 67 | else |
|---|
| 68 | { |
|---|
| 69 | __complex__ long double y; |
|---|
| 70 | |
|---|
| 71 | __real__ y = (__real__ x - __imag__ x) * (__real__ x + __imag__ x) - 1.0; |
|---|
| 72 | __imag__ y = 2.0 * __real__ x * __imag__ x; |
|---|
| 73 | |
|---|
| 74 | y = __csqrtl (y); |
|---|
| 75 | |
|---|
| 76 | __real__ y += __real__ x; |
|---|
| 77 | __imag__ y += __imag__ x; |
|---|
| 78 | |
|---|
| 79 | res = __clogl (y); |
|---|
| 80 | } |
|---|
| 81 | |
|---|
| 82 | return res; |
|---|
| 83 | } |
|---|
| 84 | weak_alias (__cacoshl, cacoshl) |
|---|
