newlib-cygwin/newlib/libm/math/w_sinh.c

121 lines
2.5 KiB
C

/* @(#)w_sinh.c 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
FUNCTION
<<sinh>>, <<sinhf>>---hyperbolic sine
INDEX
sinh
INDEX
sinhf
ANSI_SYNOPSIS
#include <math.h>
double sinh(double <[x]>);
float sinhf(float <[x]>);
TRAD_SYNOPSIS
#include <math.h>
double sinh(<[x]>)
double <[x]>;
float sinhf(<[x]>)
float <[x]>;
DESCRIPTION
<<sinh>> computes the hyperbolic sine of the argument <[x]>.
Angles are specified in radians. <<sinh>>(<[x]>) is defined as
@ifinfo
. (exp(<[x]>) - exp(-<[x]>))/2
@end ifinfo
@tex
$${e^x - e^{-x}}\over 2$$
@end tex
<<sinhf>> is identical, save that it takes and returns <<float>> values.
RETURNS
The hyperbolic sine of <[x]> is returned.
When the correct result is too large to be representable (an
overflow), <<sinh>> returns <<HUGE_VAL>> with the
appropriate sign, and sets the global value <<errno>> to
<<ERANGE>>.
You can modify error handling for these functions with <<matherr>>.
PORTABILITY
<<sinh>> is ANSI C.
<<sinhf>> is an extension.
QUICKREF
sinh ansi pure
sinhf - pure
*/
/*
* wrapper sinh(x)
*/
#include "fdlibm.h"
#include <errno.h>
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
double sinh(double x) /* wrapper sinh */
#else
double sinh(x) /* wrapper sinh */
double x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_sinh(x);
#else
double z;
struct exception exc;
z = __ieee754_sinh(x);
if(_LIB_VERSION == _IEEE_) return z;
if(!finite(z)&&finite(x)) {
/* sinh(finite) overflow */
#ifndef HUGE_VAL
#define HUGE_VAL inf
double inf = 0.0;
SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */
#endif
exc.type = OVERFLOW;
exc.name = "sinh";
exc.err = 0;
exc.arg1 = exc.arg2 = x;
if (_LIB_VERSION == _SVID_)
exc.retval = ( (x>0.0) ? HUGE : -HUGE);
else
exc.retval = ( (x>0.0) ? HUGE_VAL : -HUGE_VAL);
if (_LIB_VERSION == _POSIX_)
errno = ERANGE;
else if (!matherr(&exc)) {
errno = ERANGE;
}
if (exc.err != 0)
errno = exc.err;
return exc.retval;
} else
return z;
#endif
}
#endif /* defined(_DOUBLE_IS_32BITS) */