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diff --git a/gsl-1.9/rng/ran0.c b/gsl-1.9/rng/ran0.c
new file mode 100644
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+++ b/gsl-1.9/rng/ran0.c
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+/* rng/ran0.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_errno.h>
+#include <gsl/gsl_rng.h>
+
+/* This is an implementation of the algorithm used in Numerical
+   Recipe's ran0 generator. It is the same as MINSTD with an XOR mask
+   of 123459876 on the seed.
+
+   The period of this generator is 2^31.  
+
+   Note, if you choose a seed of 123459876 it would give a degenerate
+   series 0,0,0,0, ...  I've made that into an error. */
+
+static inline unsigned long int ran0_get (void *vstate);
+static double ran0_get_double (void *vstate);
+static void ran0_set (void *state, unsigned long int s);
+
+static const long int m = 2147483647, a = 16807, q = 127773, r = 2836;
+static const unsigned long int mask = 123459876;
+
+typedef struct
+  {
+    unsigned long int x;
+  }
+ran0_state_t;
+
+static inline unsigned long int
+ran0_get (void *vstate)
+{
+  ran0_state_t *state = (ran0_state_t *) vstate;
+
+  const unsigned long int x = state->x;
+
+  const long int h = x / q;
+  const long int t = a * (x - h * q) - h * r;
+
+  if (t < 0)
+    {
+      state->x = t + m;
+    }
+  else
+    {
+      state->x = t;
+    }
+
+  return state->x;
+}
+
+static double
+ran0_get_double (void *vstate)
+{
+  return ran0_get (vstate) / 2147483647.0 ;
+}
+
+static void
+ran0_set (void *vstate, unsigned long int s)
+{
+  ran0_state_t *state = (ran0_state_t *) vstate;
+
+  if (s == mask)
+    {
+      GSL_ERROR_VOID ("ran0 should not use seed == mask", 
+                                GSL_EINVAL);
+    }
+
+  state->x = s ^ mask;
+
+  return;
+}
+
+static const gsl_rng_type ran0_type =
+{"ran0",                        /* name */
+ 2147483646,                    /* RAND_MAX */
+ 1,                             /* RAND_MIN */
+ sizeof (ran0_state_t),
+ &ran0_set,
+ &ran0_get,
+ &ran0_get_double};
+
+const gsl_rng_type *gsl_rng_ran0 = &ran0_type;