1/* Return arc sine of a complex float type.
2 Copyright (C) 1997-2020 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, see
18 <https://www.gnu.org/licenses/>. */
19
20#include <complex.h>
21#include <math.h>
22
23
24CFLOAT
25M_DECL_FUNC (__casin) (CFLOAT x)
26{
27 CFLOAT res;
28
29 if (isnan (__real__ x) || isnan (__imag__ x))
30 {
31 if (__real__ x == 0)
32 {
33 res = x;
34 }
35 else if (isinf (__real__ x) || isinf (__imag__ x))
36 {
37 __real__ res = M_NAN;
38 __imag__ res = M_COPYSIGN (M_HUGE_VAL, __imag__ x);
39 }
40 else
41 {
42 __real__ res = M_NAN;
43 __imag__ res = M_NAN;
44 }
45 }
46 else
47 {
48 CFLOAT y;
49
50 __real__ y = -__imag__ x;
51 __imag__ y = __real__ x;
52
53 y = M_SUF (__casinh) (y);
54
55 __real__ res = __imag__ y;
56 __imag__ res = -__real__ y;
57 }
58
59 return res;
60}
61
62declare_mgen_alias (__casin, casin)
63