1 files changed, 141 insertions, 0 deletions
diff --git a/gsl-1.9/rng/zuf.c b/gsl-1.9/rng/zuf.c
new file mode 100644
index 0000000..6996b5e
--- /dev/null
+++ b/gsl-1.9/rng/zuf.c
@@ -0,0 +1,141 @@
+/* rng/zuf.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>
+
+/* It is crucial that m == n-273 mod 607 at all times;
+   For speed of execution, however, this is never enforced.
+   Instead is is set in the initializer: note 607-273=334
+   Note also that the state.u[607] is not initialized */
+
+static inline unsigned long int zuf_get (void *vstate);
+static double zuf_get_double (void *vstate);
+static void zuf_set (void *state, unsigned long int s);
+
+static const unsigned long int zuf_randmax = 16777216;  /* 2^24 */
+
+typedef struct
+  {
+    int n;
+    unsigned long int u[607];
+  }
+zuf_state_t;
+
+/* The zufall package was implemented with float's, which is to say 24
+   bits of precision.  Since I'm using long's instead, my RANDMAX
+   reflects this. */
+
+static inline unsigned long int
+zuf_get (void *vstate)
+{
+  zuf_state_t *state = (zuf_state_t *) vstate;
+  const int n = state->n;
+  const int m = (n - 273 + 607) % 607;
+  unsigned long int t = state->u[n] + state->u[m];
+
+  while (t > zuf_randmax)
+    t -= zuf_randmax;
+
+  state->u[n] = t;
+
+  if (n == 606)
+    {
+      state->n = 0;
+    }
+  else
+    {
+      state->n = n + 1;
+    }
+
+  return t;
+}
+
+static double
+zuf_get_double (void *vstate)
+{
+  return zuf_get (vstate) / 16777216.0 ;
+}
+
+static void
+zuf_set (void *vstate, unsigned long int s)
+{
+  /* A very elaborate seeding procedure is provided with the
+     zufall package; this is virtually a copy of that procedure */
+
+  /* Initialized data */
+
+  long int kl = 9373;
+  long int ij = 1802;
+
+  /* Local variables */
+  long int i, j, k, l, m;
+  double x, y;
+  long int ii, jj;
+
+  zuf_state_t *state = (zuf_state_t *) vstate;
+
+  state->n = 0;
+
+/*  generates initial seed buffer by linear congruential */
+/*  method. Taken from Marsaglia, FSU report FSU-SCRI-87-50 */
+/*  variable seed should be 0 < seed <31328 */
+
+  if (s == 0)
+    s = 1802;   /* default seed is 1802 */
+
+  ij = s;
+
+  i = ij / 177 % 177 + 2;
+  j = ij % 177 + 2;
+  k = kl / 169 % 178 + 1;
+  l = kl % 169;
+  for (ii = 0; ii < 607; ++ii)
+    {
+      x = 0.0;
+      y = 0.5;
+      /* 24 bits?? */
+      for (jj = 1; jj <= 24; ++jj)
+        {
+          m = i * j % 179 * k % 179;
+          i = j;
+          j = k;
+          k = m;
+          l = (l * 53 + 1) % 169;
+          if (l * m % 64 >= 32)
+            {
+              x += y;
+            }
+          y *= 0.5;
+        }
+      state->u[ii] = (unsigned long int) (x * zuf_randmax);
+    }
+}
+
+static const gsl_rng_type zuf_type =
+{"zuf",                         /* name */
+ 0x00ffffffUL,                  /* RAND_MAX */
+ 0,                             /* RAND_MIN */
+ sizeof (zuf_state_t),
+ &zuf_set,
+ &zuf_get,
+ &zuf_get_double};
+
+const gsl_rng_type *gsl_rng_zuf = &zuf_type;