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Diffstat (limited to 'lib/mlibc/options/ansi/generic/complex/cpow.c')
-rw-r--r-- | lib/mlibc/options/ansi/generic/complex/cpow.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/generic/complex/cpow.c b/lib/mlibc/options/ansi/generic/complex/cpow.c new file mode 100644 index 0000000..b60f7be --- /dev/null +++ b/lib/mlibc/options/ansi/generic/complex/cpow.c @@ -0,0 +1,101 @@ +/* $NetBSD: cpow.c,v 1.1 2007/08/20 16:01:35 drochner Exp $ */ + +/*- + * Copyright (c) 2007 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software written by Stephen L. Moshier. + * It is redistributed by the NetBSD Foundation by permission of the author. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * imported and modified include for newlib 2010/10/03 + * Marco Atzeri <marco_atzeri@yahoo.it> + */ + +/* +FUNCTION + <<cpow>>, <<cpowf>>---complex power + +INDEX + cpow +INDEX + cpowf + +ANSI_SYNOPSIS + #include <complex.h> + double complex cpow(double complex <[x]>, double complex <[y]>); + float complex cpowf(float complex <[x]>, float complex <[y]>); + + +DESCRIPTION + @ifnottex + The cpow functions compute the complex power function x^y + power, with a branch cut for the first parameter along the + negative real axis. + @end ifnottex + @tex + The cpow functions compute the complex power function $x^y$ + power, with a branch cut for the first parameter along the + negative real axis. + @end tex + + <<cpowf>> is identical to <<cpow>>, except that it performs + its calculations on <<floats complex>>. + +RETURNS + The cpow functions return the complex power function value. + +PORTABILITY + <<cpow>> and <<cpowf>> are ISO C99 + +QUICKREF + <<cpow>> and <<cpowf>> are ISO C99 + +*/ + + +#include <complex.h> +#include <math.h> + +double complex +cpow(double complex a, double complex z) +{ + double complex w; + double x, y, r, theta, absa, arga; + + x = creal(z); + y = cimag(z); + absa = cabs(a); + if (absa == 0.0) { + return (0.0 + 0.0 * I); + } + arga = carg(a); + r = pow(absa, x); + theta = x * arga; + if (y != 0.0) { + r = r * exp(-y * arga); + theta = theta + y * log(absa); + } + w = r * cos(theta) + (r * sin(theta)) * I; + return w; +} |