1 /* $OpenBSD: s_cexpf.c,v 1.2 2010/07/18 18:42:26 guenther 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 /* cexpf() 19 * 20 * Complex exponential function 21 * 22 * 23 * 24 * SYNOPSIS: 25 * 26 * void cexpf(); 27 * cmplxf z, w; 28 * 29 * cexpf( &z, &w ); 30 * 31 * 32 * 33 * DESCRIPTION: 34 * 35 * Returns the exponential of the complex argument z 36 * into the complex result w. 37 * 38 * If 39 * z = x + iy, 40 * r = exp(x), 41 * 42 * then 43 * 44 * w = r cos y + i r sin y. 45 * 46 * 47 * ACCURACY: 48 * 49 * Relative error: 50 * arithmetic domain # trials peak rms 51 * IEEE -10,+10 30000 1.4e-7 4.5e-8 52 * 53 */ 54 55 #include <complex.h> 56 #include <math.h> 57 58 float complex 59 cexpf(float complex z) 60 { 61 float complex w; 62 float r; 63 64 r = expf( crealf(z) ); 65 w = r * cosf( cimagf(z) ) + r * sinf( cimagf(z) ) * I; 66 return (w); 67 } 68