diff options
Diffstat (limited to 'libstdc++-v3/libmath/cexp.c')
| -rw-r--r-- | libstdc++-v3/libmath/cexp.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/libstdc++-v3/libmath/cexp.c b/libstdc++-v3/libmath/cexp.c new file mode 100644 index 00000000000..210220bc58c --- /dev/null +++ b/libstdc++-v3/libmath/cexp.c @@ -0,0 +1,111 @@ +/* Return value of complex exponential function for double complex value. */ + +/* Copyright (C) 1997-1999 Free Software Foundation, Inc. + + This file is part of the GNU ISO C++ Library. This library is free + software; you can redistribute it and/or modify it under the + terms of the GNU General Public License as published by the + Free Software Foundation; either version 2, or (at your option) + any later version. + + This 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 General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this library; see the file COPYING. If not, write to the Free + Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, + USA. + + As a special exception, you may use this file as part of a free software + library without restriction. Specifically, if other files instantiate + templates or use macros or inline functions from this file, or you compile + this file and link it with other files to produce an executable, this + file does not by itself cause the resulting executable to be covered by + the GNU General Public License. This exception does not however + invalidate any other reasons why the executable file might be covered by + the GNU General Public License. */ + + +#include <math.h> +#include "mathconf.h" + + +__complex__ double +cexp (__complex__ double x) +{ + __complex__ double retval; + + if (FINITE_P (__real__ x)) + { + /* Real part is finite. */ + if (FINITE_P (__imag__ x)) + { + /* Imaginary part is finite. */ + double exp_val = exp (__real__ x); + double sinix = sin (__imag__ x); + double cosix = cos (__imag__ x); + + if (FINITE_P (exp_val)) + { + __real__ retval = exp_val * cosix; + __imag__ retval = exp_val * sinix; + } + else + { + __real__ retval = copysign (exp_val, cosix); + __imag__ retval = copysign (exp_val, sinix); + } + } + else + { + /* If the imaginary part is +-inf or NaN and the real part + is not +-inf the result is NaN + iNaN. */ + __real__ retval = NAN; + __imag__ retval = NAN; + } + } + else if (INFINITE_P (__real__ x)) + { + /* Real part is infinite. */ + if (FINITE_P (__imag__ x)) + { + /* Imaginary part is finite. */ + double value = signbit (__real__ x) ? 0.0 : HUGE_VAL; + + if (__imag__ x == 0.0) + { + /* Imaginary part is 0.0. */ + __real__ retval = value; + __imag__ retval = __imag__ x; + } + else + { + double sinix = sin (__imag__ x); + double cosix = cos (__imag__ x); + + __real__ retval = copysign (value, cosix); + __imag__ retval = copysign (value, sinix); + } + } + else if (signbit (__real__ x) == 0) + { + __real__ retval = HUGE_VAL; + __imag__ retval = NAN; + } + else + { + __real__ retval = 0.0; + __imag__ retval = copysign (0.0, __imag__ x); + } + } + else + { + /* If the real part is NaN the result is NaN + iNaN. */ + __real__ retval = NAN; + __imag__ retval = NAN; + } + + return retval; +} |