1 /* $NetBSD: catanh.c,v 1.1 2007/08/20 16:01:32 drochner Exp $ */
2
3 /*-
4 * Copyright (c) 2007 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software written by Stephen L. Moshier.
8 * It is redistributed by the NetBSD Foundation by permission of the author.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 *
31 * imported and modified include for newlib 2010/10/03
32 * Marco Atzeri <marco_atzeri@yahoo.it>
33 */
34
35 /*
36 FUNCTION
37 <<catanh>>, <<catanhf>>---complex arc hyperbolic tangent
38
39 INDEX
40 catanh
41 INDEX
42 catanhf
43
44 SYNOPSIS
45 #include <complex.h>
46 double complex catanh(double complex <[z]>);
47 float complex catanhf(float complex <[z]>);
48
49
50 DESCRIPTION
51 These functions compute the complex arc hyperbolic tan of <[z]>,
52 with branch cuts outside the interval [-1, +1] along the
53 real axis.
54
55 <<catanhf>> is identical to <<catanh>>, except that it performs
56 its calculations on <<floats complex>>.
57
58 RETURNS
59 @ifnottex
60 These functions return the complex arc hyperbolic tangent value,
61 in the range of a strip mathematically unbounded along the
62 real axis and in the interval [-i*p/2, +i*p/2] along the
63 imaginary axis.
64 @end ifnottex
65 @tex
66 These functions return the complex arc hyperbolic tangent value,
67 in the range of a strip mathematically unbounded along the
68 real axis and in the interval [$-i\pi/2$, $+i\pi/2$] along the
69 imaginary axis.
70 @end tex
71
72 PORTABILITY
73 <<catanh>> and <<catanhf>> are ISO C99
74
75 QUICKREF
76 <<catanh>> and <<catanhf>> are ISO C99
77
78 */
79
80
81 #include <complex.h>
82
83 double complex
catanh(double complex z)84 catanh(double complex z)
85 {
86 double complex w;
87
88 w = -1.0 * (double complex) I * catan(z * (double complex) I);
89 return w;
90 }
91
