1*05a0b428SJohn Marino /* $OpenBSD: s_cexpf.c,v 1.2 2010/07/18 18:42:26 guenther Exp $ */
2*05a0b428SJohn Marino /*
3*05a0b428SJohn Marino * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
4*05a0b428SJohn Marino *
5*05a0b428SJohn Marino * Permission to use, copy, modify, and distribute this software for any
6*05a0b428SJohn Marino * purpose with or without fee is hereby granted, provided that the above
7*05a0b428SJohn Marino * copyright notice and this permission notice appear in all copies.
8*05a0b428SJohn Marino *
9*05a0b428SJohn Marino * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10*05a0b428SJohn Marino * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11*05a0b428SJohn Marino * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12*05a0b428SJohn Marino * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13*05a0b428SJohn Marino * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14*05a0b428SJohn Marino * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15*05a0b428SJohn Marino * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16*05a0b428SJohn Marino */
17*05a0b428SJohn Marino
18*05a0b428SJohn Marino /* cexpf()
19*05a0b428SJohn Marino *
20*05a0b428SJohn Marino * Complex exponential function
21*05a0b428SJohn Marino *
22*05a0b428SJohn Marino *
23*05a0b428SJohn Marino *
24*05a0b428SJohn Marino * SYNOPSIS:
25*05a0b428SJohn Marino *
26*05a0b428SJohn Marino * void cexpf();
27*05a0b428SJohn Marino * cmplxf z, w;
28*05a0b428SJohn Marino *
29*05a0b428SJohn Marino * cexpf( &z, &w );
30*05a0b428SJohn Marino *
31*05a0b428SJohn Marino *
32*05a0b428SJohn Marino *
33*05a0b428SJohn Marino * DESCRIPTION:
34*05a0b428SJohn Marino *
35*05a0b428SJohn Marino * Returns the exponential of the complex argument z
36*05a0b428SJohn Marino * into the complex result w.
37*05a0b428SJohn Marino *
38*05a0b428SJohn Marino * If
39*05a0b428SJohn Marino * z = x + iy,
40*05a0b428SJohn Marino * r = exp(x),
41*05a0b428SJohn Marino *
42*05a0b428SJohn Marino * then
43*05a0b428SJohn Marino *
44*05a0b428SJohn Marino * w = r cos y + i r sin y.
45*05a0b428SJohn Marino *
46*05a0b428SJohn Marino *
47*05a0b428SJohn Marino * ACCURACY:
48*05a0b428SJohn Marino *
49*05a0b428SJohn Marino * Relative error:
50*05a0b428SJohn Marino * arithmetic domain # trials peak rms
51*05a0b428SJohn Marino * IEEE -10,+10 30000 1.4e-7 4.5e-8
52*05a0b428SJohn Marino *
53*05a0b428SJohn Marino */
54*05a0b428SJohn Marino
55*05a0b428SJohn Marino #include <complex.h>
56*05a0b428SJohn Marino #include <math.h>
57*05a0b428SJohn Marino
58*05a0b428SJohn Marino float complex
cexpf(float complex z)59*05a0b428SJohn Marino cexpf(float complex z)
60*05a0b428SJohn Marino {
61*05a0b428SJohn Marino float complex w;
62*05a0b428SJohn Marino float r;
63*05a0b428SJohn Marino
64*05a0b428SJohn Marino r = expf( crealf(z) );
65*05a0b428SJohn Marino w = r * cosf( cimagf(z) ) + r * sinf( cimagf(z) ) * I;
66*05a0b428SJohn Marino return (w);
67*05a0b428SJohn Marino }
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