OpenLibm/src/s_csin.c
Ed Schouten 7e5585aaca Rename openlibm.h to openlibm_math.h.
This is a bit more consistent with the naming of the other header files
(openlibm_complex.h and openlibm_fenv.h). Re-add an openlibm.h header
that includes all of the public headers as a shorthand.

Fix up all of the source files to include <openlibm_math.h> instead of
<openlibm.h>. While there, fix ordering of the includes.
2015-01-11 23:37:01 +01:00

91 lines
2 KiB
C

/* $OpenBSD: s_csin.c,v 1.6 2013/07/03 04:46:36 espie Exp $ */
/*
* Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* csin()
*
* Complex circular sine
*
*
*
* SYNOPSIS:
*
* double complex csin();
* double complex z, w;
*
* w = csin (z);
*
*
*
* DESCRIPTION:
*
* If
* z = x + iy,
*
* then
*
* w = sin x cosh y + i cos x sinh y.
*
* csin(z) = -i csinh(iz).
*
* ACCURACY:
*
* Relative error:
* arithmetic domain # trials peak rms
* DEC -10,+10 8400 5.3e-17 1.3e-17
* IEEE -10,+10 30000 3.8e-16 1.0e-16
* Also tested by csin(casin(z)) = z.
*
*/
#include <float.h>
#include <openlibm_complex.h>
#include <openlibm_math.h>
/* calculate cosh and sinh */
static void
cchsh(double x, double *c, double *s)
{
double e, ei;
if (fabs(x) <= 0.5) {
*c = cosh(x);
*s = sinh(x);
}
else {
e = exp(x);
ei = 0.5/e;
e = 0.5 * e;
*s = e - ei;
*c = e + ei;
}
}
double complex
csin(double complex z)
{
double complex w;
double ch, sh;
cchsh( cimag (z), &ch, &sh );
w = sin (creal(z)) * ch + (cos (creal(z)) * sh) * I;
return (w);
}
#if LDBL_MANT_DIG == DBL_MANT_DIG
__strong_alias(csinl, csin);
#endif /* LDBL_MANT_DIG == DBL_MANT_DIG */