.
[glibc/history.git] / math / s_casinhf.c
blob7037ab937c9e71cc0b0d832271c74469fd588524
1 /* Return arc hyperbole sine for float 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.
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, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
21 #include <complex.h>
22 #include <math.h>
25 __complex__ float
26 __casinhf (__complex__ float x)
28 __complex__ float res;
29 int rcls = fpclassify (__real__ x);
30 int icls = fpclassify (__imag__ x);
32 if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
34 if (icls == FP_INFINITE)
36 __real__ res = __copysignf (HUGE_VALF, __real__ x);
38 if (rcls == FP_NAN)
39 __imag__ res = __nanf ("");
40 else
41 __imag__ res = __copysignf (rcls >= FP_ZERO ? M_PI_2 : M_PI_4,
42 __imag__ x);
44 else if (rcls <= FP_INFINITE)
46 __real__ res = __real__ x;
47 if ((rcls == FP_INFINITE && icls >= FP_ZERO)
48 || (rcls == FP_NAN && icls == FP_ZERO))
49 __imag__ res = __copysignf (0.0, __imag__ x);
50 else
51 __imag__ res = __nanf ("");
53 else
55 __real__ res = __nanf ("");
56 __imag__ res = __nanf ("");
59 else if (rcls == FP_ZERO && icls == FP_ZERO)
61 res = x;
63 else
65 __complex__ float y;
67 __real__ y = (__real__ x - __imag__ x) * (__real__ x + __imag__ x) + 1.0;
68 __imag__ y = 2.0 * __real__ x * __imag__ x;
70 y = __csqrtf (y);
72 __real__ y += __real__ x;
73 __imag__ y += __imag__ x;
75 res = __clogf (y);
78 return res;
80 #ifndef __casinhf
81 weak_alias (__casinhf, casinhf)
82 #endif