1 /* $OpenBSD: s_csinh.c,v 1.6 2013/07/03 04:46:36 espie Exp $ */
2 /*
3 * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /* csinh
19 *
20 * Complex hyperbolic sine
21 *
22 *
23 *
24 * SYNOPSIS:
25 *
26 * double complex csinh();
27 * double complex z, w;
28 *
29 * w = csinh (z);
30 *
31 * DESCRIPTION:
32 *
33 * csinh z = (cexp(z) - cexp(-z))/2
34 * = sinh x * cos y + i cosh x * sin y .
35 *
36 * ACCURACY:
37 *
38 * Relative error:
39 * arithmetic domain # trials peak rms
40 * IEEE -10,+10 30000 3.1e-16 8.2e-17
41 *
42 */
43
44 #include <complex.h>
45 #include <float.h>
46 #include <math.h>
47
48 double complex
csinh(double complex z)49 csinh(double complex z)
50 {
51 double complex w;
52 double x, y;
53
54 x = creal(z);
55 y = cimag(z);
56 w = sinh (x) * cos (y) + (cosh (x) * sin (y)) * I;
57 return (w);
58 }
59
60 #if LDBL_MANT_DIG == DBL_MANT_DIG
61 __strong_alias(csinhl, csinh);
62 #endif /* LDBL_MANT_DIG == DBL_MANT_DIG */
63