1/* mpfr_copysign -- Produce a value with the magnitude of x and sign bit of y 2 3Copyright 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. 4Contributed by the Arenaire and Cacao projects, INRIA. 5 6This file is part of the GNU MPFR Library. 7 8The GNU MPFR Library is free software; you can redistribute it and/or modify 9it under the terms of the GNU Lesser General Public License as published by 10the Free Software Foundation; either version 3 of the License, or (at your 11option) any later version. 12 13The GNU MPFR Library is distributed in the hope that it will be useful, but 14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16License for more details. 17 18You should have received a copy of the GNU Lesser General Public License 19along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 2151 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23#include "mpfr-impl.h" 24 25 /* 26 The computation of z with magnitude of x and sign of y: 27 z = (-1)^signbit(y) * abs(x), i.e. with the same sign bit as y, 28 even if z is a NaN. 29 Note: This function implements copysign from the IEEE-754 standard 30 when no rounding occurs (e.g. if PREC(z) >= PREC(x)). 31 */ 32 33#undef mpfr_copysign 34int 35mpfr_copysign (mpfr_ptr z, mpfr_srcptr x, mpfr_srcptr y, mpfr_rnd_t rnd_mode) 36{ 37 return mpfr_set4 (z, x, rnd_mode, MPFR_SIGN (y)); 38} 39