Mercurial > hg > CbC > CbC_gcc
diff libquadmath/math/catanq.c @ 68:561a7518be6b
update gcc-4.6
author | Nobuyasu Oshiro <dimolto@cr.ie.u-ryukyu.ac.jp> |
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date | Sun, 21 Aug 2011 07:07:55 +0900 |
parents | |
children | 1830386684a0 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libquadmath/math/catanq.c Sun Aug 21 07:07:55 2011 +0900 @@ -0,0 +1,81 @@ +/* Return arc tangent of complex __float128 value. + Copyright (C) 1997, 1998 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 Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include "quadmath-imp.h" + + +__complex128 +catanq (__complex128 x) +{ + __complex128 res; + int rcls = fpclassifyq (__real__ x); + int icls = fpclassifyq (__imag__ x); + + if (rcls <= QUADFP_INFINITE || icls <= QUADFP_INFINITE) + { + if (rcls == QUADFP_INFINITE) + { + __real__ res = copysignq (M_PI_2q, __real__ x); + __imag__ res = copysignq (0.0, __imag__ x); + } + else if (icls == QUADFP_INFINITE) + { + if (rcls >= QUADFP_ZERO) + __real__ res = copysignq (M_PI_2q, __real__ x); + else + __real__ res = nanq (""); + __imag__ res = copysignq (0.0, __imag__ x); + } + else if (icls == QUADFP_ZERO || icls == QUADFP_INFINITE) + { + __real__ res = nanq (""); + __imag__ res = copysignq (0.0, __imag__ x); + } + else + { + __real__ res = nanq (""); + __imag__ res = nanq (""); + } + } + else if (rcls == QUADFP_ZERO && icls == QUADFP_ZERO) + { + res = x; + } + else + { + __float128 r2, num, den; + + r2 = __real__ x * __real__ x; + + den = 1 - r2 - __imag__ x * __imag__ x; + + __real__ res = 0.5 * atan2q (2.0 * __real__ x, den); + + num = __imag__ x + 1.0; + num = r2 + num * num; + + den = __imag__ x - 1.0; + den = r2 + den * den; + + __imag__ res = 0.25 * logq (num / den); + } + + return res; +}