1 files changed, 132 insertions, 0 deletions
diff --git a/gsl-1.9/rng/ran3.c b/gsl-1.9/rng/ran3.c
new file mode 100644
index 0000000..7ccc47c
--- /dev/null
+++ b/gsl-1.9/rng/ran3.c
@@ -0,0 +1,132 @@
+/* rng/ran3.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 an implementation of the algorithm used in Knuths's
+   subtractive generator, with the Numerical Recipe's ran3 paramters.
+   It is a subtractive lagged fibonnaci generator. */
+
+static inline unsigned long int ran3_get (void *vstate);
+static double ran3_get_double (void *vstate);
+static void ran3_set (void *state, unsigned long int s);
+
+#define M_BIG 1000000000
+#define M_SEED 161803398
+
+typedef struct
+  {
+    unsigned int x;
+    unsigned int y;
+    unsigned long int buffer[56];
+  }
+ran3_state_t;
+
+static inline unsigned long int
+ran3_get (void *vstate)
+{
+  ran3_state_t *state = (ran3_state_t *) vstate;
+  long int j;
+
+  state->x++;
+
+  if (state->x == 56)
+    state->x = 1;
+
+  state->y++;
+
+  if (state->y == 56)
+    state->y = 1;
+
+  j = state->buffer[state->x] - state->buffer[state->y];
+
+  if (j < 0)
+    j += M_BIG;
+
+  state->buffer[state->x] = j;
+
+  return j;
+}
+
+static double
+ran3_get_double (void *vstate)
+{
+  return ran3_get (vstate) / (double) M_BIG ;
+}
+
+static void
+ran3_set (void *vstate, unsigned long int s)
+{
+  ran3_state_t *state = (ran3_state_t *) vstate;
+  int i, i1;
+  long int j, k;
+
+  if (s == 0)
+    s = 1;      /* default seed is 1 */
+
+  j = (M_SEED - s) % M_BIG;
+
+  /* the zeroth element is never used, but we initialize it for
+     consistency between states */
+
+  state->buffer[0] = 0; 
+
+  state->buffer[55] = j;
+
+  k = 1;
+  for (i = 1; i < 55; i++)
+    {
+      int n = (21 * i) % 55;
+      state->buffer[n] = k;
+      k = j - k;
+      if (k < 0)
+        k += M_BIG;
+      j = state->buffer[n];
+
+    }
+
+  for (i1 = 0; i1 < 4; i1++)
+    {
+      for (i = 1; i < 56; i++)
+        {
+          long int t = state->buffer[i] - state->buffer[1 + (i + 30) % 55];
+          if (t < 0)
+            t += M_BIG;
+          state->buffer[i] = t;
+        }
+    }
+
+  state->x = 0;
+  state->y = 31;
+
+  return;
+}
+
+static const gsl_rng_type ran3_type =
+{"ran3",                        /* name */
+ M_BIG,                         /* RAND_MAX */
+ 0,                             /* RAND_MIN */
+ sizeof (ran3_state_t),
+ &ran3_set,
+ &ran3_get,
+ &ran3_get_double};
+
+const gsl_rng_type *gsl_rng_ran3 = &ran3_type;