| Elliott Hughes | 9ee6adb | 2016-03-11 14:49:13 -0800 | [diff] [blame^] | 1 | /* $NetBSD: cpow.c,v 1.1 2007/08/20 16:01:35 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 | |
| 32 | #include "../src/namespace.h" |
| 33 | #include <complex.h> |
| 34 | #include <math.h> |
| 35 | |
| 36 | double complex |
| 37 | cpow(double complex a, double complex z) |
| 38 | { |
| 39 | double complex w; |
| 40 | double x, y, r, theta, absa, arga; |
| 41 | |
| 42 | x = creal(z); |
| 43 | y = cimag(z); |
| 44 | absa = cabs(a); |
| 45 | if (absa == 0.0) { |
| 46 | return (0.0 + 0.0 * I); |
| 47 | } |
| 48 | arga = carg(a); |
| 49 | r = pow(absa, x); |
| 50 | theta = x * arga; |
| 51 | if (y != 0.0) { |
| 52 | r = r * exp(-y * arga); |
| 53 | theta = theta + y * log(absa); |
| 54 | } |
| 55 | w = r * cos(theta) + (r * sin(theta)) * I; |
| 56 | return w; |
| 57 | } |