GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/s_cpow.c Lines: 0 11 0.0 %
Date: 2017-11-13 Branches: 0 4 0.0 %

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/*	$OpenBSD: s_cpow.c,v 1.7 2016/09/12 19:47:02 guenther Exp $	*/
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/*
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 * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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/*							cpow
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 *
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 *	Complex power function
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 *
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 *
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 *
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 * SYNOPSIS:
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 *
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 * double complex cpow();
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 * double complex a, z, w;
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 *
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 * w = cpow (a, z);
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 *
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 *
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 *
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 * DESCRIPTION:
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 *
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 * Raises complex A to the complex Zth power.
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 * Definition is per AMS55 # 4.2.8,
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 * analytically equivalent to cpow(a,z) = cexp(z clog(a)).
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 *
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 * ACCURACY:
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 *
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 *                      Relative error:
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 * arithmetic   domain     # trials      peak         rms
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 *    IEEE      -10,+10     30000       9.4e-15     1.5e-15
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 *
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 */
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#include <complex.h>
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#include <float.h>
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#include <math.h>
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double complex
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cpow(double complex a, double complex z)
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{
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	double complex w;
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	double x, y, r, theta, absa, arga;
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	x = creal (z);
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	y = cimag (z);
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	absa = cabs (a);
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	if (absa == 0.0) {
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		return (0.0 + 0.0 * I);
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	}
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	arga = carg (a);
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	r = pow (absa, x);
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	theta = x * arga;
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	if (y != 0.0) {
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		r = r * exp (-y * arga);
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		theta = theta + y * log (absa);
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	}
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	w = r * cos (theta) + (r * sin (theta)) * I;
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	return (w);
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}
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DEF_STD(cpow);
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LDBL_MAYBE_UNUSED_CLONE(cpow);