1 /* mpfr_cmp -- compare two floating-point numbers
3 Copyright 1999, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 Contributed by the Arenaire and Caramel projects, INRIA.
6 This file is part of the GNU MPFR Library.
8 The GNU MPFR Library is free software; you can redistribute it and/or modify
9 it under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or (at your
11 option) any later version.
13 The GNU MPFR Library is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
16 License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
20 http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
23 #include "mpfr-impl.h"
25 /* returns 0 iff b = sign(s) * c
26 a positive value iff b > sign(s) * c
27 a negative value iff b < sign(s) * c
28 returns 0 and sets erange flag if b and/or c is NaN.
32 mpfr_cmp3 (mpfr_srcptr b, mpfr_srcptr c, int s)
38 s = MPFR_MULT_SIGN( s , MPFR_SIGN(c) );
40 if (MPFR_ARE_SINGULAR(b, c))
42 if (MPFR_IS_NAN (b) || MPFR_IS_NAN (c))
47 else if (MPFR_IS_INF(b))
49 if (MPFR_IS_INF(c) && s == MPFR_SIGN(b) )
54 else if (MPFR_IS_INF(c))
56 else if (MPFR_IS_ZERO(b))
57 return MPFR_IS_ZERO(c) ? 0 : -s;
58 else /* necessarily c=0 */
61 /* b and c are real numbers */
62 if (s != MPFR_SIGN(b))
65 /* now signs are equal */
67 be = MPFR_GET_EXP (b);
68 ce = MPFR_GET_EXP (c);
74 /* both signs and exponents are equal */
76 bn = (MPFR_PREC(b)-1)/GMP_NUMB_BITS;
77 cn = (MPFR_PREC(c)-1)/GMP_NUMB_BITS;
82 for ( ; bn >= 0 && cn >= 0; bn--, cn--)
89 for ( ; bn >= 0; bn--)
92 for ( ; cn >= 0; cn--)
101 mpfr_cmp (mpfr_srcptr b, mpfr_srcptr c)
103 return mpfr_cmp3 (b, c, 1);