1 /* Complex sine 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.
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.
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.
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/>. */
24 #include <math_private.h>
28 __csin (__complex__ double x)
30 __complex__ double retval;
31 int negate = signbit (__real__ x);
32 int rcls = fpclassify (__real__ x);
33 int icls = fpclassify (__imag__ x);
35 __real__ x = fabs (__real__ x);
37 if (__builtin_expect (icls >= FP_ZERO, 1))
39 /* Imaginary part is finite. */
40 if (__builtin_expect (rcls >= FP_ZERO, 1))
42 /* Real part is finite. */
43 double sinh_val = __ieee754_sinh (__imag__ x);
44 double cosh_val = __ieee754_cosh (__imag__ x);
47 __sincos (__real__ x, &sinix, &cosix);
49 __real__ retval = cosh_val * sinix;
50 __imag__ retval = sinh_val * cosix;
53 __real__ retval = -__real__ retval;
59 /* Imaginary part is 0.0. */
60 __real__ retval = __nan ("");
61 __imag__ retval = __imag__ x;
63 if (rcls == FP_INFINITE)
64 feraiseexcept (FE_INVALID);
68 __real__ retval = __nan ("");
69 __imag__ retval = __nan ("");
71 feraiseexcept (FE_INVALID);
75 else if (icls == FP_INFINITE)
77 /* Imaginary part is infinite. */
80 /* Real part is 0.0. */
81 __real__ retval = __copysign (0.0, negate ? -1.0 : 1.0);
82 __imag__ retval = __imag__ x;
84 else if (rcls > FP_ZERO)
86 /* Real part is finite. */
89 __sincos (__real__ x, &sinix, &cosix);
91 __real__ retval = __copysign (HUGE_VAL, sinix);
92 __imag__ retval = __copysign (HUGE_VAL, cosix);
95 __real__ retval = -__real__ retval;
96 if (signbit (__imag__ x))
97 __imag__ retval = -__imag__ retval;
101 /* The addition raises the invalid exception. */
102 __real__ retval = __nan ("");
103 __imag__ retval = HUGE_VAL;
105 if (rcls == FP_INFINITE)
106 feraiseexcept (FE_INVALID);
112 __real__ retval = __copysign (0.0, negate ? -1.0 : 1.0);
114 __real__ retval = __nan ("");
115 __imag__ retval = __nan ("");
120 weak_alias (__csin, csin)
121 #ifdef NO_LONG_DOUBLE
122 strong_alias (__csin, __csinl)
123 weak_alias (__csin, csinl)