1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2011 David Schultz
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /*
30 * Hyperbolic tangent of a complex argument z. See s_ctanh.c for details.
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD: head/lib/msun/src/s_ctanhf.c 336362 2018-07-17 07:42:14Z bde $");
35
36 #include <complex.h>
37 #include <math.h>
38
39 #include "math_private.h"
40
41 float complex
ctanhf(float complex z)42 ctanhf(float complex z)
43 {
44 float x, y;
45 float t, beta, s, rho, denom;
46 uint32_t hx, ix;
47
48 x = crealf(z);
49 y = cimagf(z);
50
51 GET_FLOAT_WORD(hx, x);
52 ix = hx & 0x7fffffff;
53
54 if (ix >= 0x7f800000) {
55 if (ix & 0x7fffff)
56 return (CMPLXF(nan_mix(x, y),
57 y == 0 ? y : nan_mix(x, y)));
58 SET_FLOAT_WORD(x, hx - 0x40000000);
59 return (CMPLXF(x,
60 copysignf(0, isinf(y) ? y : sinf(y) * cosf(y))));
61 }
62
63 if (!isfinite(y))
64 return (CMPLXF(y - y, y - y));
65
66 if (ix >= 0x41300000) { /* |x| >= 11 */
67 float exp_mx = expf(-fabsf(x));
68 return (CMPLXF(copysignf(1, x),
69 4 * sinf(y) * cosf(y) * exp_mx * exp_mx));
70 }
71
72 t = tanf(y);
73 beta = 1.0 + t * t;
74 s = sinhf(x);
75 rho = sqrtf(1 + s * s);
76 denom = 1 + beta * s * s;
77 return (CMPLXF((beta * rho * s) / denom, t / denom));
78 }
79
80 float complex
ctanf(float complex z)81 ctanf(float complex z)
82 {
83
84 z = ctanhf(CMPLXF(cimagf(z), crealf(z)));
85 return (CMPLXF(cimagf(z), crealf(z)));
86 }
87
88