math/s_ccosh.c

   1 /* Complex cosine hyperbole function for double.
   2    Copyright (C) 1997, 2011 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 <fenv.h>
  23 #include <math.h>
  24
  25 #include <math_private.h>
  26
  27
  28 __complex__ double
  29 __ccosh (__complex__ double x)
  30 {
  31   __complex__ double retval;
  32   int rcls = fpclassify (__real__ x);
  33   int icls = fpclassify (__imag__ x);
  34
  35   if (__builtin_expect (rcls >= FP_ZERO, 1))
  36     {
  37       /* Real part is finite.  */
  38       if (__builtin_expect (icls >= FP_ZERO, 1))
  39         {
  40           /* Imaginary part is finite.  */
  41           double sinh_val = __ieee754_sinh (__real__ x);
  42           double cosh_val = __ieee754_cosh (__real__ x);
  43           double sinix, cosix;
  44
  45           __sincos (__imag__ x, &sinix, &cosix);
  46
  47           __real__ retval = cosh_val * cosix;
  48           __imag__ retval = sinh_val * sinix;
  49         }
  50       else
  51         {
  52           __imag__ retval = __real__ x == 0.0 ? 0.0 : __nan ("");
  53           __real__ retval = __nan ("") + __nan ("");
  54
  55           if (icls == FP_INFINITE)
  56             feraiseexcept (FE_INVALID);
  57         }
  58     }
  59   else if (rcls == FP_INFINITE)
  60     {
  61       /* Real part is infinite.  */
  62       if (__builtin_expect (icls > FP_ZERO, 1))
  63         {
  64           /* Imaginary part is finite.  */
  65           double sinix, cosix;
  66
  67           __sincos (__imag__ x, &sinix, &cosix);
  68
  69           __real__ retval = __copysign (HUGE_VAL, cosix);
  70           __imag__ retval = (__copysign (HUGE_VAL, sinix)
  71                              * __copysign (1.0, __real__ x));
  72         }
  73       else if (icls == FP_ZERO)
  74         {
  75           /* Imaginary part is 0.0.  */
  76           __real__ retval = HUGE_VAL;
  77           __imag__ retval = __imag__ x * __copysign (1.0, __real__ x);
  78         }
  79       else
  80         {
  81           /* The addition raises the invalid exception.  */
  82           __real__ retval = HUGE_VAL;
  83           __imag__ retval = __nan ("") + __nan ("");
  84
  85           if (icls == FP_INFINITE)
  86             feraiseexcept (FE_INVALID);
  87         }
  88     }
  89   else
  90     {
  91       __real__ retval = __nan ("");
  92       __imag__ retval = __imag__ x == 0.0 ? __imag__ x : __nan ("");
  93     }
  94
  95   return retval;
  96 }
  97 weak_alias (__ccosh, ccosh)
  98 #ifdef NO_LONG_DOUBLE
  99 strong_alias (__ccosh, __ccoshl)
 100 weak_alias (__ccosh, ccoshl)
 101 #endif