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diff --git a/gsl-1.9/randist/logarithmic.c b/gsl-1.9/randist/logarithmic.c
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+++ b/gsl-1.9/randist/logarithmic.c
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+/* randist/logarithmic.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 <math.h>
+#include <gsl/gsl_rng.h>
+#include <gsl/gsl_randist.h>
+
+/* Logarithmic distribution 
+
+   prob(n) =   p^n / (n log(1/(1-p)) for n = 1, 2, 3, ...
+
+   We use Kemp's second accelerated generator, from Luc Devroye's book
+   on "Non-Uniform Random Variate Generation", Springer */
+
+unsigned int
+gsl_ran_logarithmic (const gsl_rng * r, const double p)
+{
+  double c = log (1-p) ;
+
+  double v = gsl_rng_uniform_pos (r);
+  
+  if (v >= p)
+    {
+      return 1 ;
+    }
+  else
+    {
+      double u = gsl_rng_uniform_pos (r);      
+      double q = 1 - exp (c * u);
+
+      if (v <= q*q)
+        {
+          double x = 1 + log(v)/log(q) ;
+          return x ;
+        }
+      else if (v <= q)
+        {
+          return 2;
+        }
+      else
+        {
+          return 1 ;
+        }
+    }
+}
+
+double
+gsl_ran_logarithmic_pdf (const unsigned int k, const double p)
+{
+  if (k == 0)
+    {
+      return 0 ;
+    }
+  else 
+    {
+      double P = pow(p, (double)k) / (double) k / log(1/(1-p)) ;
+      return P;
+    }
+}