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Annotation of OpenXM_contrib/gmp/randlc2s.c, Revision 1.1.1.1

1.1       ohara       1: /* gmp_randinit_lc_2exp_size -- initialize a random state with a linear
                      2:    congruential generator of a requested size.
                      3:
                      4: Copyright 1999, 2000, 2001 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: #include <stdio.h> /* for NULL */
                     24: #include "gmp.h"
                     25: #include "gmp-impl.h"
                     26:
                     27:
                     28: /* Array of LC-schemes, ordered in increasing order of the first
                     29:    member (the 'm2exp' value).  The end of the array is indicated with
                     30:    an entry containing all zeros.  */
                     31:
                     32: /* All multipliers are in the range 0.01*m and 0.99*m, and are
                     33: congruent to 5 (mod 8).
                     34: They all pass the spectral test with Vt >= 2^(30/t) and merit >= 1.
                     35: (Up to and including 196 bits, merit is >= 3.)  */
                     36:
                     37: struct __gmp_rand_lc_scheme_struct
                     38: {
                     39:   unsigned long int m2exp;     /* Modulus is 2 ^ m2exp. */
                     40:   const char *astr;            /* Multiplier in string form. */
                     41:   unsigned long int c;         /* Addend. */
                     42: };
                     43:
                     44: static const struct __gmp_rand_lc_scheme_struct __gmp_rand_lc_scheme[] =
                     45: {
                     46:   {32, "29CF535",           1},
                     47:   {33, "51F666D",           1},
                     48:   {34, "A3D73AD",           1},
                     49:   {35, "147E5B85",          1},
                     50:   {36, "28F725C5",          1},
                     51:   {37, "51EE3105",          1},
                     52:   {38, "A3DD5CDD",          1},
                     53:   {39, "147AF833D",         1},
                     54:   {40, "28F5DA175",         1},
                     55:   {56, "AA7D735234C0DD",  1},
                     56:   {64, "BAECD515DAF0B49D", 1},
                     57:   {100, "292787EBD3329AD7E7575E2FD", 1},
                     58:   {128, "48A74F367FA7B5C8ACBB36901308FA85", 1},
                     59:   {156, "78A7FDDDC43611B527C3F1D760F36E5D7FC7C45", 1},
                     60:   {196, "41BA2E104EE34C66B3520CE706A56498DE6D44721E5E24F5", 1},
                     61:   {200, "4E5A24C38B981EAFE84CD9D0BEC48E83911362C114F30072C5", 1},
                     62:   {256, "AF66BA932AAF58A071FD8F0742A99A0C76982D648509973DB802303128A14CB5", 1},
                     63:   {0, NULL, 0}                 /* End of array. */
                     64: };
                     65:
                     66: int
                     67: gmp_randinit_lc_2exp_size (gmp_randstate_t rstate, unsigned long size)
                     68: {
                     69:   const struct __gmp_rand_lc_scheme_struct *sp;
                     70:   mpz_t a;
                     71:
                     72:   /* Pick a scheme.  */
                     73:   for (sp = __gmp_rand_lc_scheme; sp->m2exp != 0; sp++)
                     74:     if (sp->m2exp / 2 >= size)
                     75:       goto found;
                     76:   return 0;
                     77:
                     78:  found:
                     79:   /* Install scheme.  */
                     80:   mpz_init_set_str (a, sp->astr, 16);
                     81:   gmp_randinit_lc_2exp (rstate, a, sp->c, sp->m2exp);
                     82:   mpz_clear (a);
                     83:   return 1;
                     84: }