1*2fe8fb19SBen Gras /* $NetBSD: cpow.c,v 1.1 2007/08/20 16:01:35 drochner Exp $ */
2*2fe8fb19SBen Gras
3*2fe8fb19SBen Gras /*-
4*2fe8fb19SBen Gras * Copyright (c) 2007 The NetBSD Foundation, Inc.
5*2fe8fb19SBen Gras * All rights reserved.
6*2fe8fb19SBen Gras *
7*2fe8fb19SBen Gras * This code is derived from software written by Stephen L. Moshier.
8*2fe8fb19SBen Gras * It is redistributed by the NetBSD Foundation by permission of the author.
9*2fe8fb19SBen Gras *
10*2fe8fb19SBen Gras * Redistribution and use in source and binary forms, with or without
11*2fe8fb19SBen Gras * modification, are permitted provided that the following conditions
12*2fe8fb19SBen Gras * are met:
13*2fe8fb19SBen Gras * 1. Redistributions of source code must retain the above copyright
14*2fe8fb19SBen Gras * notice, this list of conditions and the following disclaimer.
15*2fe8fb19SBen Gras * 2. Redistributions in binary form must reproduce the above copyright
16*2fe8fb19SBen Gras * notice, this list of conditions and the following disclaimer in the
17*2fe8fb19SBen Gras * documentation and/or other materials provided with the distribution.
18*2fe8fb19SBen Gras *
19*2fe8fb19SBen Gras * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*2fe8fb19SBen Gras * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*2fe8fb19SBen Gras * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*2fe8fb19SBen Gras * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*2fe8fb19SBen Gras * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*2fe8fb19SBen Gras * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*2fe8fb19SBen Gras * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*2fe8fb19SBen Gras * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*2fe8fb19SBen Gras * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*2fe8fb19SBen Gras * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*2fe8fb19SBen Gras * POSSIBILITY OF SUCH DAMAGE.
30*2fe8fb19SBen Gras */
31*2fe8fb19SBen Gras
32*2fe8fb19SBen Gras #include "../src/namespace.h"
33*2fe8fb19SBen Gras #include <complex.h>
34*2fe8fb19SBen Gras #include <math.h>
35*2fe8fb19SBen Gras
36*2fe8fb19SBen Gras double complex
cpow(double complex a,double complex z)37*2fe8fb19SBen Gras cpow(double complex a, double complex z)
38*2fe8fb19SBen Gras {
39*2fe8fb19SBen Gras double complex w;
40*2fe8fb19SBen Gras double x, y, r, theta, absa, arga;
41*2fe8fb19SBen Gras
42*2fe8fb19SBen Gras x = creal(z);
43*2fe8fb19SBen Gras y = cimag(z);
44*2fe8fb19SBen Gras absa = cabs(a);
45*2fe8fb19SBen Gras if (absa == 0.0) {
46*2fe8fb19SBen Gras return (0.0 + 0.0 * I);
47*2fe8fb19SBen Gras }
48*2fe8fb19SBen Gras arga = carg(a);
49*2fe8fb19SBen Gras r = pow(absa, x);
50*2fe8fb19SBen Gras theta = x * arga;
51*2fe8fb19SBen Gras if (y != 0.0) {
52*2fe8fb19SBen Gras r = r * exp(-y * arga);
53*2fe8fb19SBen Gras theta = theta + y * log(absa);
54*2fe8fb19SBen Gras }
55*2fe8fb19SBen Gras w = r * cos(theta) + (r * sin(theta)) * I;
56*2fe8fb19SBen Gras return w;
57*2fe8fb19SBen Gras }
58