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Annotation of OpenXM_contrib/gmp/mpf/pow_ui.c, Revision 1.1.1.1

1.1       maekawa     1: /* mpf_pow_ui -- Compute b^e.
                      2:
                      3: Copyright (C) 1998, 1999 Free Software Foundation, Inc.
                      4:
                      5: This file is part of the GNU MP Library.
                      6:
                      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 2.1 of the License, or (at your
                     10: option) any later version.
                     11:
                     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.
                     16:
                     17: You should have received a copy of the GNU Lesser General Public License
                     18: along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
                     19: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
                     20: MA 02111-1307, USA. */
                     21:
                     22: #include "gmp.h"
                     23: #include "gmp-impl.h"
                     24:
                     25: void
                     26: #if __STDC__
                     27: mpf_pow_ui (mpf_ptr r, mpf_srcptr b, unsigned long int e)
                     28: #else
                     29: mpf_pow_ui (r, b, e)
                     30:      mpf_ptr r;
                     31:      mpf_srcptr b;
                     32:      unsigned long int e;
                     33: #endif
                     34: {
                     35:   mpf_t b2;
                     36:   unsigned long int e2;
                     37:
                     38:   mpf_init2 (b2, mpf_get_prec (r));
                     39:   mpf_set (b2, b);
                     40:   mpf_set_ui (r, 1);
                     41:
                     42:   if ((e & 1) != 0)
                     43:     mpf_set (r, b2);
                     44:   for (e2 = e >> 1; e2 != 0; e2 >>= 1)
                     45:     {
                     46:       mpf_mul (b2, b2, b2);
                     47:       if ((e2 & 1) != 0)
                     48:        mpf_mul (r, r, b2);
                     49:     }
                     50:
                     51:   mpf_clear (b2);
                     52: }