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diff --git a/gsl-1.9/randist/lognormal.c b/gsl-1.9/randist/lognormal.c
new file mode 100644
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+++ b/gsl-1.9/randist/lognormal.c
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+/* randist/lognormal.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_math.h>
+#include <gsl/gsl_rng.h>
+#include <gsl/gsl_randist.h>
+
+/* The lognormal distribution has the form 
+
+   p(x) dx = 1/(x * sqrt(2 pi sigma^2)) exp(-(ln(x) - zeta)^2/2 sigma^2) dx
+
+   for x > 0. Lognormal random numbers are the exponentials of
+   gaussian random numbers */
+
+double
+gsl_ran_lognormal (const gsl_rng * r, const double zeta, const double sigma)
+{
+  double u, v, r2, normal, z;
+
+  do
+    {
+      /* choose x,y in uniform square (-1,-1) to (+1,+1) */
+
+      u = -1 + 2 * gsl_rng_uniform (r);
+      v = -1 + 2 * gsl_rng_uniform (r);
+
+      /* see if it is in the unit circle */
+      r2 = u * u + v * v;
+    }
+  while (r2 > 1.0 || r2 == 0);
+
+  normal = u * sqrt (-2.0 * log (r2) / r2);
+
+  z =  exp (sigma * normal + zeta);
+
+  return z;
+}
+
+double
+gsl_ran_lognormal_pdf (const double x, const double zeta, const double sigma)
+{
+  if (x <= 0)
+    {
+      return 0 ;
+    }
+  else
+    {
+      double u = (log (x) - zeta)/sigma;
+      double p = 1 / (x * fabs(sigma) * sqrt (2 * M_PI)) * exp (-(u * u) /2);
+      return p;
+    }
+}