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Diffstat (limited to 'sysdeps/generic/s_ctanf.c')
-rw-r--r-- | sysdeps/generic/s_ctanf.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/sysdeps/generic/s_ctanf.c b/sysdeps/generic/s_ctanf.c new file mode 100644 index 0000000000..750d3511b9 --- /dev/null +++ b/sysdeps/generic/s_ctanf.c @@ -0,0 +1,70 @@ +/* Complex tangent function for float. + 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 Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <complex.h> +#include <fenv.h> +#include <math.h> + +#include "math_private.h" + + +__complex__ float +__ctanf (__complex__ float x) +{ + __complex__ float res; + + if (!isfinite (__real__ x) || !isfinite (__imag__ x)) + { + if (__isinff (__imag__ x)) + { + __real__ res = __copysignf (0.0, __real__ x); + __imag__ res = __copysignf (1.0, __imag__ x); + } + else if (__real__ x == 0.0) + { + res = x; + } + else + { + __real__ res = __nanf (""); + __imag__ res = __nanf (""); + +#ifdef FE_INVALID + if (__isinff (__real__ x)) + feraiseexcept (FE_INVALID); +#endif + } + } + else + { + float sin2rx, cos2rx; + float den; + + __sincosf (2.0 * __real__ x, &sin2rx, &cos2rx); + + den = cos2rx + __ieee754_coshf (2.0 * __imag__ x); + + __real__ res = sin2rx / den; + __imag__ res = __ieee754_sinhf (2.0 * __imag__ x) / den; + } + + return res; +} +weak_alias (__ctanf, ctanf) |