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

Line Branch Exec Source
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/*	$OpenBSD: s_clog.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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/*							clog.c
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 *
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 *	Complex natural logarithm
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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 clog();
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 * double complex z, w;
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 *
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 * w = clog (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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 * Returns complex logarithm to the base e (2.718...) of
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 * the complex argument x.
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 *
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 * If z = x + iy, r = sqrt( x**2 + y**2 ),
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 * then
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 *       w = log(r) + i arctan(y/x).
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 *
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 * The arctangent ranges from -PI to +PI.
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 *
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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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 *    DEC       -10,+10      7000       8.5e-17     1.9e-17
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 *    IEEE      -10,+10     30000       5.0e-15     1.1e-16
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 *
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 * Larger relative error can be observed for z near 1 +i0.
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 * In IEEE arithmetic the peak absolute error is 5.2e-16, rms
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 * absolute error 1.0e-16.
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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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clog(double complex z)
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{
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	double complex w;
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	double p, rr;
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	/*rr = sqrt( z->r * z->r  +  z->i * z->i );*/
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	rr = cabs(z);
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	p = log(rr);
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	rr = atan2 (cimag (z), creal (z));
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	w = p + rr * I;
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	return (w);
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}
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DEF_STD(clog);
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LDBL_MAYBE_CLONE(clog);