From 9d13fb2413921c713f83efe331e8e4d219c62c6b Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Wed, 14 Dec 2005 15:06:39 +0000 Subject: Moved to csu/errno-loc.c. --- math/s_cproj.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 math/s_cproj.c (limited to 'math/s_cproj.c') diff --git a/math/s_cproj.c b/math/s_cproj.c new file mode 100644 index 0000000000..8e7ca41df8 --- /dev/null +++ b/math/s_cproj.c @@ -0,0 +1,51 @@ +/* Compute projection of complex double value to Riemann sphere. + Copyright (C) 1997, 1999 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 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 +#include + + +__complex__ double +__cproj (__complex__ double x) +{ + __complex__ double res; + + if (isnan (__real__ x) && isnan (__imag__ x)) + return x; + else if (!isfinite (__real__ x) || !isfinite (__imag__ x)) + { + __real__ res = INFINITY; + __imag__ res = __copysign (0.0, __imag__ x); + } + else + { + double den = __real__ x * __real__ x + __imag__ x * __imag__ x + 1.0; + + __real__ res = (2.0 * __real__ x) / den; + __imag__ res = (2.0 * __imag__ x) / den; + } + + return res; +} +weak_alias (__cproj, cproj) +#ifdef NO_LONG_DOUBLE +strong_alias (__cproj, __cprojl) +weak_alias (__cproj, cprojl) +#endif -- cgit 1.4.1