OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [newlib-1.17.0/] [newlib/] [libc/] [sys/] [linux/] [cmath/] [s_catanh.c] - Blame information for rev 816

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 148 jeremybenn
/* Return arc hyperbole tangent for double value.
2
   Copyright (C) 1997 Free Software Foundation, Inc.
3
   This file is part of the GNU C Library.
4
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
 
6
   The GNU C Library is free software; you can redistribute it and/or
7
   modify it under the terms of the GNU Lesser General Public
8
   License as published by the Free Software Foundation; either
9
   version 2.1 of the License, or (at your option) any later version.
10
 
11
   The GNU C Library is distributed in the hope that it will be useful,
12
   but WITHOUT ANY WARRANTY; without even the implied warranty of
13
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14
   Lesser General Public License for more details.
15
 
16
   You should have received a copy of the GNU Lesser General Public
17
   License along with the GNU C Library; if not, write to the Free
18
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19
   02111-1307 USA.  */
20
 
21
#include <complex.h>
22
#include <math.h>
23
 
24
#include "math_private.h"
25
 
26
 
27
__complex__ double
28
__catanh (__complex__ double x)
29
{
30
  __complex__ double res;
31
  int rcls = fpclassify (__real__ x);
32
  int icls = fpclassify (__imag__ x);
33
 
34
  if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
35
    {
36
      if (icls == FP_INFINITE)
37
        {
38
          __real__ res = __copysign (0.0, __real__ x);
39
          __imag__ res = __copysign (M_PI_2, __imag__ x);
40
        }
41
      else if (rcls == FP_INFINITE || rcls == FP_ZERO)
42
        {
43
          __real__ res = __copysign (0.0, __real__ x);
44
          if (icls >= FP_ZERO)
45
            __imag__ res = __copysign (M_PI_2, __imag__ x);
46
          else
47
            __imag__ res = __nan ("");
48
        }
49
      else
50
        {
51
          __real__ res = __nan ("");
52
          __imag__ res = __nan ("");
53
        }
54
    }
55
  else if (rcls == FP_ZERO && icls == FP_ZERO)
56
    {
57
      res = x;
58
    }
59
  else
60
    {
61
      double i2, num, den;
62
 
63
      i2 = __imag__ x * __imag__ x;
64
 
65
      num = 1.0 + __real__ x;
66
      num = i2 + num * num;
67
 
68
      den = 1.0 - __real__ x;
69
      den = i2 + den * den;
70
 
71
      __real__ res = 0.25 * (__ieee754_log (num) - __ieee754_log (den));
72
 
73
      den = 1 - __real__ x * __real__ x - i2;
74
 
75
      __imag__ res = 0.5 * __ieee754_atan2 (2.0 * __imag__ x, den);
76
    }
77
 
78
  return res;
79
}
80
weak_alias (__catanh, catanh)
81
#ifdef NO_LONG_DOUBLE
82
strong_alias (__catanh, __catanhl)
83
weak_alias (__catanh, catanhl)
84
#endif

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.