glibc/math/s_csin.c
2005-12-14 15:06:39 +00:00

132 lines
3.2 KiB
C

/* Complex sine 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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <complex.h>
#include <fenv.h>
#include <math.h>
#include "math_private.h"
__complex__ double
__csin (__complex__ double x)
{
__complex__ double retval;
int negate = signbit (__real__ x);
int rcls = fpclassify (__real__ x);
int icls = fpclassify (__imag__ x);
__real__ x = fabs (__real__ x);
if (icls >= FP_ZERO)
{
/* Imaginary part is finite. */
if (rcls >= FP_ZERO)
{
/* Real part is finite. */
double sinh_val = __ieee754_sinh (__imag__ x);
double cosh_val = __ieee754_cosh (__imag__ x);
double sinix, cosix;
__sincos (__real__ x, &sinix, &cosix);
__real__ retval = cosh_val * sinix;
__imag__ retval = sinh_val * cosix;
if (negate)
__real__ retval = -__real__ retval;
}
else
{
if (icls == FP_ZERO)
{
/* Imaginary part is 0.0. */
__real__ retval = __nan ("");
__imag__ retval = __imag__ x;
#ifdef FE_INVALID
if (rcls == FP_INFINITE)
feraiseexcept (FE_INVALID);
#endif
}
else
{
__real__ retval = __nan ("");
__imag__ retval = __nan ("");
#ifdef FE_INVALID
feraiseexcept (FE_INVALID);
#endif
}
}
}
else if (icls == FP_INFINITE)
{
/* Imaginary part is infinite. */
if (rcls == FP_ZERO)
{
/* Real part is 0.0. */
__real__ retval = __copysign (0.0, negate ? -1.0 : 1.0);
__imag__ retval = __imag__ x;
}
else if (rcls > FP_ZERO)
{
/* Real part is finite. */
double sinix, cosix;
__sincos (__real__ x, &sinix, &cosix);
__real__ retval = __copysign (HUGE_VAL, sinix);
__imag__ retval = __copysign (HUGE_VAL, cosix);
if (negate)
__real__ retval = -__real__ retval;
if (signbit (__imag__ x))
__imag__ retval = -__imag__ retval;
}
else
{
/* The addition raises the invalid exception. */
__real__ retval = __nan ("");
__imag__ retval = HUGE_VAL;
#ifdef FE_INVALID
if (rcls == FP_INFINITE)
feraiseexcept (FE_INVALID);
#endif
}
}
else
{
if (rcls == FP_ZERO)
__real__ retval = __copysign (0.0, negate ? -1.0 : 1.0);
else
__real__ retval = __nan ("");
__imag__ retval = __nan ("");
}
return retval;
}
weak_alias (__csin, csin)
#ifdef NO_LONG_DOUBLE
strong_alias (__csin, __csinl)
weak_alias (__csin, csinl)
#endif