mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 01:00:07 +00:00
83 lines
2.2 KiB
C
83 lines
2.2 KiB
C
/* Return arc hyperbole tangent for float value.
|
|
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 <math.h>
|
|
|
|
#include "math_private.h"
|
|
|
|
|
|
__complex__ float
|
|
__catanhf (__complex__ float x)
|
|
{
|
|
__complex__ float res;
|
|
int rcls = fpclassify (__real__ x);
|
|
int icls = fpclassify (__imag__ x);
|
|
|
|
if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
|
|
{
|
|
if (icls == FP_INFINITE)
|
|
{
|
|
__real__ res = __copysignf (0.0, __real__ x);
|
|
__imag__ res = __copysignf (M_PI_2, __imag__ x);
|
|
}
|
|
else if (rcls == FP_INFINITE || rcls == FP_ZERO)
|
|
{
|
|
__real__ res = __copysignf (0.0, __real__ x);
|
|
if (icls >= FP_ZERO)
|
|
__imag__ res = __copysignf (M_PI_2, __imag__ x);
|
|
else
|
|
__imag__ res = __nanf ("");
|
|
}
|
|
else
|
|
{
|
|
__real__ res = __nanf ("");
|
|
__imag__ res = __nanf ("");
|
|
}
|
|
}
|
|
else if (rcls == FP_ZERO && icls == FP_ZERO)
|
|
{
|
|
res = x;
|
|
}
|
|
else
|
|
{
|
|
float i2, num, den;
|
|
|
|
i2 = __imag__ x * __imag__ x;
|
|
|
|
num = 1.0 + __real__ x;
|
|
num = i2 + num * num;
|
|
|
|
den = 1.0 - __real__ x;
|
|
den = i2 + den * den;
|
|
|
|
__real__ res = 0.25 * (__ieee754_logf (num) - __ieee754_logf (den));
|
|
|
|
den = 1 - __real__ x * __real__ x - i2;
|
|
|
|
__imag__ res = 0.5 * __ieee754_atan2f (2.0 * __imag__ x, den);
|
|
}
|
|
|
|
return res;
|
|
}
|
|
#ifndef __catanhf
|
|
weak_alias (__catanhf, catanhf)
|
|
#endif
|