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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <complex.h>
  21 #include <fenv.h>
  22 #include <math.h>
  23
  24 #include <math_private.h>
  25
  26
  27 __complex__ double
  28 __ccosh (__complex__ double x)
  29 {
  30   __complex__ double retval;
  31   int rcls = fpclassify (__real__ x);
  32   int icls = fpclassify (__imag__ x);
  33
  34   if (__builtin_expect (rcls >= FP_ZERO, 1))
  35     {
  36       /* Real part is finite.  */
  37       if (__builtin_expect (icls >= FP_ZERO, 1))
  38         {
  39           /* Imaginary part is finite.  */
  40           double sinh_val = __ieee754_sinh (__real__ x);
  41           double cosh_val = __ieee754_cosh (__real__ x);
  42           double sinix, cosix;
  43
  44           __sincos (__imag__ x, &sinix, &cosix);
  45
  46           __real__ retval = cosh_val * cosix;
  47           __imag__ retval = sinh_val * sinix;
  48         }
  49       else
  50         {
  51           __imag__ retval = __real__ x == 0.0 ? 0.0 : __nan ("");
  52           __real__ retval = __nan ("") + __nan ("");
  53
  54           if (icls == FP_INFINITE)
  55             feraiseexcept (FE_INVALID);
  56         }
  57     }
  58   else if (rcls == FP_INFINITE)
  59     {
  60       /* Real part is infinite.  */
  61       if (__builtin_expect (icls > FP_ZERO, 1))
  62         {
  63           /* Imaginary part is finite.  */
  64           double sinix, cosix;
  65
  66           __sincos (__imag__ x, &sinix, &cosix);
  67
  68           __real__ retval = __copysign (HUGE_VAL, cosix);
  69           __imag__ retval = (__copysign (HUGE_VAL, sinix)
  70                              * __copysign (1.0, __real__ x));
  71         }
  72       else if (icls == FP_ZERO)
  73         {
  74           /* Imaginary part is 0.0.  */
  75           __real__ retval = HUGE_VAL;
  76           __imag__ retval = __imag__ x * __copysign (1.0, __real__ x);
  77         }
  78       else
  79         {
  80           /* The addition raises the invalid exception.  */
  81           __real__ retval = HUGE_VAL;
  82           __imag__ retval = __nan ("") + __nan ("");
  83
  84           if (icls == FP_INFINITE)
  85             feraiseexcept (FE_INVALID);
  86         }
  87     }
  88   else
  89     {
  90       __real__ retval = __nan ("");
  91       __imag__ retval = __imag__ x == 0.0 ? __imag__ x : __nan ("");
  92     }
  93
  94   return retval;
  95 }
  96 weak_alias (__ccosh, ccosh)
  97 #ifdef NO_LONG_DOUBLE
  98 strong_alias (__ccosh, __ccoshl)
  99 weak_alias (__ccosh, ccoshl)
 100 #endif