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diff --git a/gsl-1.9/rng/randu.c b/gsl-1.9/rng/randu.c
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+++ b/gsl-1.9/rng/randu.c
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+/* rng/randu.c
+ * 
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000 James Theiler, Brian Gough
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ * 
+ * This program 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
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <gsl/gsl_rng.h>
+
+/* This is a reincarnation of the infamously bad RANDU generator.
+   The sequence is,
+
+   x_{n+1} = (a x_n) mod m
+
+   with a = 65539 and m = 2^31 = 2147483648. The seed specifies
+   the initial value, x_1.
+
+   The theoretical value of x_{10001} is 1623524161.
+
+   The period of this generator is 2^29.
+
+   Note: Knuth describes this generator as "really horrible". 
+
+   From: Park and Miller, "Random Number Generators: Good ones are
+   hard to find" Communications of the ACM, October 1988, Volume 31,
+   No 10, pages 1192-1201. */
+
+static inline unsigned long int randu_get (void *vstate);
+static double randu_get_double (void *vstate);
+static void randu_set (void *state, unsigned long int s);
+
+static const long int a = 65539;
+/* static const unsigned long int m = 2147483648UL; */
+
+typedef struct
+  {
+    unsigned long int x;
+  }
+randu_state_t;
+
+static inline unsigned long int
+randu_get (void *vstate)
+{
+  randu_state_t *state = (randu_state_t *) vstate;
+
+  /* The following line relies on unsigned 32-bit arithmetic */
+
+  state->x = (a * state->x) & 0x7fffffffUL;
+
+  return state->x;
+}
+
+static double
+randu_get_double (void *vstate)
+{
+  return randu_get (vstate) / 2147483648.0 ;
+}
+
+static void
+randu_set (void *vstate, unsigned long int s)
+{
+  randu_state_t *state = (randu_state_t *) vstate;
+
+  if (s == 0)
+    s = 1;      /* default seed is 1 */
+
+  state->x = s;
+
+  return;
+}
+
+static const gsl_rng_type randu_type =
+{"randu",                       /* name */
+ 0x7fffffffUL,                  /* RAND_MAX */
+ 1,                             /* RAND_MIN */
+ sizeof (randu_state_t),
+ &randu_set,
+ &randu_get,
+ &randu_get_double};
+
+const gsl_rng_type *gsl_rng_randu = &randu_type;