Annotation of OpenXM_contrib/gmp/mpfr/pow.c, Revision 1.1
1.1 ! maekawa 1: /* mpfr_pow_ui, mpfr_ui_pow_ui -- compute the power of a floating-point
! 2: number or machine integer
! 3:
! 4: Copyright (C) 1999 PolKA project, Inria Lorraine and Loria
! 5:
! 6: This file is part of the MPFR Library.
! 7:
! 8: The MPFR Library is free software; you can redistribute it and/or modify
! 9: it under the terms of the GNU Library General Public License as published by
! 10: the Free Software Foundation; either version 2 of the License, or (at your
! 11: option) any later version.
! 12:
! 13: The 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 Library General Public
! 16: License for more details.
! 17:
! 18: You should have received a copy of the GNU Library General Public License
! 19: along with the MPFR 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: #include <stdio.h>
! 24: #include "gmp.h"
! 25: #include "mpfr.h"
! 26:
! 27: /* sets x to y^n */
! 28: void
! 29: #if __STDC__
! 30: mpfr_pow_ui (mpfr_ptr x, mpfr_srcptr y, unsigned int n, unsigned char rnd)
! 31: #else
! 32: mpfr_pow_ui (x, y, n, rnd)
! 33: mpfr_ptr x;
! 34: mpfr_srcptr y;
! 35: unsigned int n;
! 36: unsigned char rnd;
! 37: #endif
! 38: {
! 39: int i;
! 40:
! 41: if (n==0) { mpfr_set_ui(x, 1, rnd); return; }
! 42: mpfr_set(x, y, rnd);
! 43: for (i=0;(1<<i)<=n;i++);
! 44: /* now 2^(i-1) <= n < 2^i */
! 45: for (i-=2; i>=0; i--) {
! 46: mpfr_mul(x, x, x, rnd);
! 47: if (n & (1<<i)) mpfr_mul(x, x, y, rnd);
! 48: }
! 49: return;
! 50: }
! 51:
! 52: /* sets x to y^n */
! 53: void mpfr_ui_pow_ui (mpfr_ptr x, unsigned int y, unsigned int n,
! 54: unsigned char rnd)
! 55: {
! 56: int i;
! 57:
! 58: if (n==0) { mpfr_set_ui(x, 1, rnd); return; }
! 59: mpfr_set_ui(x, y, rnd);
! 60: for (i=0;(1<<i)<=n;i++);
! 61: /* now 2^(i-1) <= n < 2^i */
! 62: for (i-=2; i>=0; i--) {
! 63: mpfr_mul(x, x, x, rnd);
! 64: if (n & (1<<i)) mpfr_mul_ui(x, x, y, rnd);
! 65: }
! 66: return;
! 67: }
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