glibc/sysdeps/libm-ieee754/s_csinh.c

103 lines
2.6 KiB
C

/* Complex sine hyperbole function for double.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <complex.h>
#include <math.h>
__complex__ double
__csinh (__complex__ double x)
{
__complex__ double retval;
int negate = signbit (__real__ x);
__real__ x = fabs (__real__ x);
if (isfinite (__real__ x))
{
if (isfinite (__imag__ x))
{
double exp_val = __exp (__real__ x);
double rec_exp_val = 1.0 / exp_val;
__real__ retval = 0.5 * (exp_val - rec_exp_val) * __cos (__imag__ x);
__imag__ retval = 0.5 * (exp_val - rec_exp_val) * __sin (__imag__ x);
if (negate)
__real__ retval = -__real__ retval;
}
else
{
if (__real__ x == 0)
{
__real__ retval = __copysign (0.0, negate ? -1.0 : 1.0);
__imag__ retval = __nan ("") + __nan ("");
}
else
{
__real__ retval = __nan ("");
__imag__ retval = __nan ("");
}
}
}
else if (__isinf (__real__ x))
{
if (__imag__ x == 0.0)
{
__real__ retval = negate ? -HUGE_VAL : HUGE_VAL;
__imag__ retval = __imag__ x;
}
else if (isfinite (__imag__ x))
{
__real__ retval = __copysign (HUGE_VAL, __cos (__imag__ x));
__imag__ retval = __copysign (HUGE_VAL, __sin (__imag__ x));
if (negate)
__real__ retval = -__real__ retval;
}
else
{
/* The addition raises the invalid exception. */
__real__ retval = HUGE_VAL;
__imag__ retval = __nan ("") + __nan ("");
}
}
else
{
if (__imag__ x == 0.0)
{
__real__ retval = __nan ("");
__imag__ retval = __imag__ x;
}
else
{
__real__ retval = __nan ("");
__imag__ retval = __nan ("");
}
}
return retval;
}
weak_alias (__csinh, csinh)
#ifdef NO_LONG_DOUBLE
strong_alias (__csinh, __csinhl)
weak_alias (__csinh, csinhl)
#endif