Annotation of OpenXM_contrib/gmp/mpf/get_ui.c, Revision 1.1
1.1 ! ohara 1: /* mpf_get_ui -- mpf to ulong conversion */
! 2:
! 3: /*
! 4: Copyright 2001, 2002 Free Software Foundation, Inc.
! 5:
! 6: This file is part of the GNU MP Library.
! 7:
! 8: The GNU MP 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 2.1 of the License, or (at your
! 11: option) any later version.
! 12:
! 13: The GNU MP 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.
! 17:
! 18: You should have received a copy of the GNU Lesser General Public License
! 19: along with the GNU MP Library; see the file COPYING.LIB. If not, write to
! 20: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
! 21: MA 02111-1307, USA.
! 22: */
! 23:
! 24: #include "gmp.h"
! 25: #include "gmp-impl.h"
! 26:
! 27:
! 28: /* Any fraction bits are truncated, meaning simply discarded.
! 29:
! 30: For values bigger than a ulong, the low bits are returned (the low
! 31: absolute value bits actually), like mpz_get_ui, but this isn't
! 32: documented.
! 33:
! 34: Notice this is equivalent to mpz_set_f + mpz_get_ui. */
! 35:
! 36:
! 37: unsigned long
! 38: mpf_get_ui (mpf_srcptr f)
! 39: {
! 40: mp_size_t size, abs_size;
! 41: mp_exp_t exp;
! 42:
! 43: size = SIZ (f);
! 44: if (size == 0)
! 45: return 0L;
! 46:
! 47: /* fraction alone truncates to zero */
! 48: exp = EXP (f);
! 49: if (exp <= 0)
! 50: return 0L;
! 51:
! 52: /* exponent bigger than available data means low limb zero */
! 53: abs_size = ABS (size);
! 54: if (exp > abs_size)
! 55: return 0L;
! 56:
! 57: return (unsigned long) PTR(f)[abs_size-exp];
! 58: }
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>