1 /* Complex tangent function for float. 2 Copyright (C) 1997 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__ float 29 __ctanf (__complex__ float x) 30 { 31 __complex__ float res; 32 33 if (!isfinite (__real__ x) || !isfinite (__imag__ x)) 34 { 35 if (__isinff (__imag__ x)) 36 { 37 __real__ res = copysignf (0.0, __real__ x); 38 __imag__ res = copysignf (1.0, __imag__ x); 39 } 40 else if (__real__ x == 0.0) 41 { 42 res = x; 43 } 44 else 45 { 46 __real__ res = nanf (""); 47 __imag__ res = nanf (""); 48 49 #ifdef FE_INVALID 50 if (__isinff (__real__ x)) 51 feraiseexcept (FE_INVALID); 52 #endif 53 } 54 } 55 else 56 { 57 float sin2rx, cos2rx; 58 float den; 59 60 sincosf (2.0 * __real__ x, &sin2rx, &cos2rx); 61 62 den = cos2rx + coshf (2.0 * __imag__ x); 63 64 __real__ res = sin2rx / den; 65 __imag__ res = sinhf (2.0 * __imag__ x) / den; 66 } 67 68 return res; 69 } 70 #ifndef __ctanf 71 weak_alias (__ctanf, ctanf) 72 #endif 73