mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-19 03:05:15 +00:00
102 lines
3.1 KiB
C
102 lines
3.1 KiB
C
/* $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;
|
|
}
|