mirror of
https://github.com/autc04/Retro68.git
synced 2024-12-22 04:30:03 +00:00
92 lines
2.7 KiB
C
92 lines
2.7 KiB
C
/* $NetBSD: ctan.c,v 1.1 2007/08/20 16:01:37 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
|
|
<<ctan>>, <<ctanf>>---complex tangent
|
|
|
|
INDEX
|
|
ctan
|
|
INDEX
|
|
ctanf
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <complex.h>
|
|
double complex ctan(double complex <[z]>);
|
|
float complex ctanf(float complex <[z]>);
|
|
|
|
|
|
DESCRIPTION
|
|
These functions compute the complex tangent of <[z]>.
|
|
|
|
<<ctanf>> is identical to <<ctan>>, except that it performs
|
|
its calculations on <<floats complex>>.
|
|
|
|
RETURNS
|
|
These functions return the complex tangent value.
|
|
|
|
PORTABILITY
|
|
<<ctan>> and <<ctanf>> are ISO C99
|
|
|
|
QUICKREF
|
|
<<ctan>> and <<ctanf>> are ISO C99
|
|
|
|
*/
|
|
|
|
|
|
#include <complex.h>
|
|
#include <math.h>
|
|
#include "cephes_subr.h"
|
|
|
|
double complex
|
|
ctan(double complex z)
|
|
{
|
|
double complex w;
|
|
double d;
|
|
|
|
d = cos(2.0 * creal(z)) + cosh(2.0 * cimag(z));
|
|
|
|
if (fabs(d) < 0.25)
|
|
d = _ctans(z);
|
|
|
|
if (d == 0.0) {
|
|
/* mtherr ("ctan", OVERFLOW); */
|
|
w = HUGE_VAL + HUGE_VAL * I;
|
|
return w;
|
|
}
|
|
|
|
w = sin(2.0 * creal(z)) / d + (sinh(2.0 * cimag(z)) / d) * I;
|
|
return w;
|
|
}
|