1 /* mpf_reldiff -- Generate the relative difference of two floats.
3 Copyright 1996, 2001, 2004, 2005 Free Software Foundation, Inc.
5 This file is part of the GNU MP Library.
7 The GNU MP Library is free software; you can redistribute it and/or modify
8 it under the terms of the GNU Lesser General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or (at your
10 option) any later version.
12 The GNU MP Library is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
15 License for more details.
17 You should have received a copy of the GNU Lesser General Public License
18 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
24 /* The precision we use for d = x-y is based on what mpf_div will want from
25 the dividend. It calls mpn_tdiv_qr to produce a quotient of rprec+1
26 limbs. So rprec+1 == dsize - xsize + 1, hence dprec = rprec+xsize. */
29 mpf_reldiff (mpf_t rdiff, mpf_srcptr x, mpf_srcptr y)
31 if (UNLIKELY (SIZ(x) == 0))
33 mpf_set_ui (rdiff, (unsigned long int) (mpf_sgn (y) != 0));
42 dprec = PREC(rdiff) + ABSIZ(x);
43 ASSERT (PREC(rdiff)+1 == dprec - ABSIZ(x) + 1);
46 PTR(d) = TMP_ALLOC_LIMBS (dprec + 1);
50 mpf_div (rdiff, d, x);