newlib-cygwin/winsup/cygwin/math/coshl.c

46 lines
874 B
C

/**
* This file has no copyright assigned and is placed in the Public Domain.
* This file is part of the mingw-w64 runtime package.
* No warranty is given; refer to the file DISCLAIMER.PD within this package.
*/
#include "cephes_mconf.h"
#ifndef _SET_ERRNO
#define _SET_ERRNO(x)
#endif
long double coshl(long double x)
{
long double y;
int x_class = fpclassify (x);
if (x_class == FP_NAN)
{
errno = EDOM;
return x;
}
else if (x_class == FP_INFINITE)
{
errno = ERANGE;
return INFINITY;
}
x = fabsl (x);
if (x > (MAXLOGL + LOGE2L))
{
errno = ERANGE;
#ifdef INFINITIES
return (INFINITYL);
#else
return (MAXNUML);
#endif
}
if (x >= (MAXLOGL - LOGE2L))
{
y = expl(0.5L * x);
y = (0.5L * y) * y;
return y;
}
y = expl(x);
y = 0.5L * (y + 1.0L / y);
return y;
}