1/* mpf_neg -- Negate a float. 2 3Copyright 1993, 1994, 1995, 2001 Free Software Foundation, Inc. 4 5This file is part of the GNU MP Library. 6 7The GNU MP Library is free software; you can redistribute it and/or modify 8it under the terms of the GNU Lesser General Public License as published by 9the Free Software Foundation; either version 3 of the License, or (at your 10option) any later version. 11 12The GNU MP Library is distributed in the hope that it will be useful, but 13WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 14or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 15License for more details. 16 17You should have received a copy of the GNU Lesser General Public License 18along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ 19 20#include "gmp.h" 21#include "gmp-impl.h" 22 23void 24mpf_neg (mpf_ptr r, mpf_srcptr u) 25{ 26 mp_size_t size; 27 28 size = -u->_mp_size; 29 if (r != u) 30 { 31 mp_size_t prec; 32 mp_size_t asize; 33 mp_ptr rp, up; 34 35 prec = r->_mp_prec + 1; /* lie not to lose precision in assignment */ 36 asize = ABS (size); 37 rp = r->_mp_d; 38 up = u->_mp_d; 39 40 if (asize > prec) 41 { 42 up += asize - prec; 43 asize = prec; 44 } 45 46 MPN_COPY (rp, up, asize); 47 r->_mp_exp = u->_mp_exp; 48 size = size >= 0 ? asize : -asize; 49 } 50 r->_mp_size = size; 51} 52