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authorTorbjorn Granlund <tege@gmplib.org>2010-11-11 09:56:42 +0100
committerTorbjorn Granlund <tege@gmplib.org>2010-11-11 09:56:42 +0100
commitfb80223734ba92b2a182f29b00751e509dbece06 (patch)
tree014931d1dc5a4f1024644986a489c3859f1df727 /rand/randlc2s.c
parent5b824f09ff34399acf7458217a903c928f7eb83b (diff)
downloadgmp-fb80223734ba92b2a182f29b00751e509dbece06.tar.gz
Move global random file to new 'rand' subdirectory.
Diffstat (limited to 'rand/randlc2s.c')
-rw-r--r--rand/randlc2s.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/rand/randlc2s.c b/rand/randlc2s.c
new file mode 100644
index 000000000..4dcde73a2
--- /dev/null
+++ b/rand/randlc2s.c
@@ -0,0 +1,82 @@
+/* gmp_randinit_lc_2exp_size -- initialize a random state with a linear
+ congruential generator of a requested size.
+
+Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 3 of the License, or (at your
+option) any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
+
+#include <stdio.h> /* for NULL */
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+/* Array of LC-schemes, ordered in increasing order of the first
+ member (the 'm2exp' value). The end of the array is indicated with
+ an entry containing all zeros. */
+
+/* All multipliers are in the range 0.01*m and 0.99*m, and are
+congruent to 5 (mod 8).
+They all pass the spectral test with Vt >= 2^(30/t) and merit >= 1.
+(Up to and including 196 bits, merit is >= 3.) */
+
+struct __gmp_rand_lc_scheme_struct
+{
+ unsigned long int m2exp; /* Modulus is 2 ^ m2exp. */
+ const char *astr; /* Multiplier in string form. */
+ unsigned long int c; /* Addend. */
+};
+
+static const struct __gmp_rand_lc_scheme_struct __gmp_rand_lc_scheme[] =
+{
+ {32, "29CF535", 1},
+ {33, "51F666D", 1},
+ {34, "A3D73AD", 1},
+ {35, "147E5B85", 1},
+ {36, "28F725C5", 1},
+ {37, "51EE3105", 1},
+ {38, "A3DD5CDD", 1},
+ {39, "147AF833D", 1},
+ {40, "28F5DA175", 1},
+ {56, "AA7D735234C0DD", 1},
+ {64, "BAECD515DAF0B49D", 1},
+ {100, "292787EBD3329AD7E7575E2FD", 1},
+ {128, "48A74F367FA7B5C8ACBB36901308FA85", 1},
+ {156, "78A7FDDDC43611B527C3F1D760F36E5D7FC7C45", 1},
+ {196, "41BA2E104EE34C66B3520CE706A56498DE6D44721E5E24F5", 1},
+ {200, "4E5A24C38B981EAFE84CD9D0BEC48E83911362C114F30072C5", 1},
+ {256, "AF66BA932AAF58A071FD8F0742A99A0C76982D648509973DB802303128A14CB5", 1},
+ {0, NULL, 0} /* End of array. */
+};
+
+int
+gmp_randinit_lc_2exp_size (gmp_randstate_t rstate, mp_bitcnt_t size)
+{
+ const struct __gmp_rand_lc_scheme_struct *sp;
+ mpz_t a;
+
+ /* Pick a scheme. */
+ for (sp = __gmp_rand_lc_scheme; sp->m2exp != 0; sp++)
+ if (sp->m2exp / 2 >= size)
+ goto found;
+ return 0;
+
+ found:
+ /* Install scheme. */
+ mpz_init_set_str (a, sp->astr, 16);
+ gmp_randinit_lc_2exp (rstate, a, sp->c, sp->m2exp);
+ mpz_clear (a);
+ return 1;
+}