1 files changed, 121 insertions, 0 deletions
diff --git a/gsl-1.9/rng/fishman2x.c b/gsl-1.9/rng/fishman2x.c
new file mode 100644
index 0000000..afe0c27
--- /dev/null
+++ b/gsl-1.9/rng/fishman2x.c
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+/* rng/fishman2x.c
+ * 
+ * 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.
+ */
+
+/*
+ * This generator is taken from
+ *
+ * Donald E. Knuth
+ * The Art of Computer Programming
+ * Volume 2
+ * Third Edition
+ * Addison-Wesley
+ * Page 108
+ *
+ * It is called "Fishman - L'Ecuyer"
+ *
+ * This implementation copyright (C) 2001 Carlo Perassi
+ * and (C) 2003 Heiko Bauke.
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <gsl/gsl_rng.h>
+
+/* Fishman */
+#define AAA_F 48271UL
+#define MMM_F 0x7fffffffUL      /* 2 ^ 31 - 1 */
+#define QQQ_F 44488UL
+#define RRR_F 3399UL
+
+/* L'Ecuyer */
+#define AAA_L 40692UL
+#define MMM_L 0x7fffff07UL      /* 2 ^ 31 - 249 */
+#define QQQ_L 52774UL
+#define RRR_L 3791UL
+
+static inline unsigned long int ran_get (void *vstate);
+static double ran_get_double (void *vstate);
+static void ran_set (void *state, unsigned long int s);
+
+typedef struct
+{
+  unsigned long int x;
+  unsigned long int y;
+  unsigned long int z;
+}
+ran_state_t;
+
+static inline unsigned long int
+ran_get (void *vstate)
+{
+  ran_state_t *state = (ran_state_t *) vstate;
+
+  long int y, r;
+
+  r = RRR_F * (state->x / QQQ_F);
+  y = AAA_F * (state->x % QQQ_F) - r;
+  if (y < 0)
+    y += MMM_F;
+  state->x = y;
+
+  r = RRR_L * (state->y / QQQ_L);
+  y = AAA_L * (state->y % QQQ_L) - r;
+  if (y < 0)
+    y += MMM_L;
+  state->y = y;
+
+  state->z = (state->x > state->y) ? (state->x - state->y) :
+    MMM_F + state->x - state->y;
+
+  return state->z;
+}
+
+static double
+ran_get_double (void *vstate)
+{
+  ran_state_t *state = (ran_state_t *) vstate;
+
+  return ran_get (state) / 2147483647.0;
+}
+
+static void
+ran_set (void *vstate, unsigned long int s)
+{
+  ran_state_t *state = (ran_state_t *) vstate;
+
+  if ((s % MMM_F) == 0 || (s % MMM_L) == 0)
+    s = 1;                      /* default seed is 1 */
+
+  state->x = s % MMM_F;
+  state->y = s % MMM_L;
+  state->z = (state->x > state->y) ? (state->x - state->y) :
+    MMM_F + state->x - state->y;
+
+  return;
+}
+
+static const gsl_rng_type ran_type = {
+  "fishman2x",                  /* name */
+  MMM_F - 1,                    /* RAND_MAX */
+  0,                            /* RAND_MIN */
+  sizeof (ran_state_t),
+  &ran_set,
+  &ran_get,
+  &ran_get_double
+};
+
+const gsl_rng_type *gsl_rng_fishman2x = &ran_type;