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[/] [scarts/] [trunk/] [toolchain/] [scarts-newlib/] [newlib-1.17.0/] [newlib/] [libc/] [sys/] [linux/] [cmath/] [s_catan.c] - Blame information for rev 9

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/* Return arc tangent of complex double 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__ double
__catan (__complex__ double x)
{
  __complex__ double res;
  int rcls = fpclassify (__real__ x);
  int icls = fpclassify (__imag__ x);
 
  if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
    {
      if (rcls == FP_INFINITE)
        {
          __real__ res = __copysign (M_PI_2, __real__ x);
          __imag__ res = __copysign (0.0, __imag__ x);
        }
      else if (icls == FP_INFINITE)
        {
          if (rcls >= FP_ZERO)
            __real__ res = __copysign (M_PI_2, __real__ x);
          else
            __real__ res = __nan ("");
          __imag__ res = __copysign (0.0, __imag__ x);
        }
      else if (icls == FP_ZERO || icls == FP_INFINITE)
        {
          __real__ res = __nan ("");
          __imag__ res = __copysign (0.0, __imag__ x);
        }
      else
        {
          __real__ res = __nan ("");
          __imag__ res = __nan ("");
        }
    }
  else if (rcls == FP_ZERO && icls == FP_ZERO)
    {
      res = x;
    }
  else
    {
      double r2, num, den;
 
      r2 = __real__ x * __real__ x;
 
      den = 1 - r2 - __imag__ x * __imag__ x;
 
      __real__ res = 0.5 * __ieee754_atan2 (2.0 * __real__ x, den);
 
      num = __imag__ x + 1.0;
      num = r2 + num * num;
 
      den = __imag__ x - 1.0;
      den = r2 + den * den;
 
      __imag__ res = 0.25 * __ieee754_log (num / den);
    }
 
  return res;
}
weak_alias (__catan, catan)
#ifdef NO_LONG_DOUBLE
strong_alias (__catan, __catanl)
weak_alias (__catan, catanl)
#endif

Line No.	Rev	Author	Line
1	9	jlechner	`/* Return arc tangent of complex 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			`__catan (__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 (rcls == FP_INFINITE)`
37			`{`
38			`__real__ res = __copysign (M_PI_2, __real__ x);`
39			`__imag__ res = __copysign (0.0, __imag__ x);`
40			`}`
41			`else if (icls == FP_INFINITE)`
42			`{`
43			`if (rcls >= FP_ZERO)`
44			`__real__ res = __copysign (M_PI_2, __real__ x);`
45			`else`
46			`__real__ res = __nan ("");`
47			`__imag__ res = __copysign (0.0, __imag__ x);`
48			`}`
49			`else if (icls == FP_ZERO \|\| icls == FP_INFINITE)`
50			`{`
51			`__real__ res = __nan ("");`
52			`__imag__ res = __copysign (0.0, __imag__ x);`
53			`}`
54			`else`
55			`{`
56			`__real__ res = __nan ("");`
57			`__imag__ res = __nan ("");`
58			`}`
59			`}`
60			`else if (rcls == FP_ZERO && icls == FP_ZERO)`
61			`{`
62			`res = x;`
63			`}`
64			`else`
65			`{`
66			`double r2, num, den;`
67
68			`r2 = __real__ x * __real__ x;`
69
70			`den = 1 - r2 - __imag__ x * __imag__ x;`
71
72			`__real__ res = 0.5 * __ieee754_atan2 (2.0 * __real__ x, den);`
73
74			`num = __imag__ x + 1.0;`
75			`num = r2 + num * num;`
76
77			`den = __imag__ x - 1.0;`
78			`den = r2 + den * den;`
79
80			`__imag__ res = 0.25 * __ieee754_log (num / den);`
81			`}`
82
83			`return res;`
84			`}`
85			`weak_alias (__catan, catan)`
86			`#ifdef NO_LONG_DOUBLE`
87			`strong_alias (__catan, __catanl)`
88			`weak_alias (__catan, catanl)`
89			`#endif`

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[/] [scarts/] [trunk/] [toolchain/] [scarts-newlib/] [newlib-1.17.0/] [newlib/] [libc/] [sys/] [linux/] [cmath/] [s_catan.c] - Blame information for rev 9