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diff --git a/gnuradio-runtime/lib/math/random.cc b/gnuradio-runtime/lib/math/random.cc
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+++ b/gnuradio-runtime/lib/math/random.cc
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+/* -*- c++ -*- */
+/*
+ * Copyright 2002 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio 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 3, or (at your option)
+ * any later version.
+ *
+ * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+/*
+ *  Copyright 1997 Massachusetts Institute of Technology
+ *
+ *  Permission to use, copy, modify, distribute, and sell this software and its
+ *  documentation for any purpose is hereby granted without fee, provided that
+ *  the above copyright notice appear in all copies and that both that
+ *  copyright notice and this permission notice appear in supporting
+ *  documentation, and that the name of M.I.T. not be used in advertising or
+ *  publicity pertaining to distribution of the software without specific,
+ *  written prior permission.  M.I.T. makes no representations about the
+ *  suitability of this software for any purpose.  It is provided "as is"
+ *  without express or implied warranty.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <math.h>
+#include <gnuradio/random.h>
+
+namespace gr {
+
+#define IA 16807
+#define IM 2147483647
+#define AM (1.0/IM)
+#define IQ 127773
+#define IR 2836
+#define NDIV (1+(IM-1)/NTAB)
+#define EPS 1.2e-7
+#define RNMX (1.0-EPS)
+
+  random::random(long seed)
+  {
+    reseed(seed);
+  }
+
+  void
+  random::reseed(long seed)
+  {
+    d_seed = seed;
+    d_iy = 0;
+    for(int i = 0; i < NTAB; i++)
+      d_iv[i] = 0;
+    d_iset = 0;
+    d_gset = 0;
+  }
+
+  /*
+   * This looks like it returns a uniform random deviate between 0.0 and 1.0
+   * It looks similar to code from "Numerical Recipes in C".
+   */
+  float
+  random::ran1()
+  {
+    int j;
+    long k;
+    float temp;
+
+    if(d_seed <= 0 || !d_iy)  {
+      if(-d_seed < 1)
+        d_seed=1;
+      else
+        d_seed = -d_seed;
+      for(j=NTAB+7;j>=0;j--) {
+        k=d_seed/IQ;
+        d_seed=IA*(d_seed-k*IQ)-IR*k;
+        if(d_seed < 0)
+          d_seed += IM;
+        if(j < NTAB)
+          d_iv[j] = d_seed;
+      }
+      d_iy=d_iv[0];
+    }
+    k=(d_seed)/IQ;
+    d_seed=IA*(d_seed-k*IQ)-IR*k;
+    if(d_seed < 0)
+      d_seed += IM;
+    j=d_iy/NDIV;
+    d_iy=d_iv[j];
+    d_iv[j] = d_seed;
+    temp=AM * d_iy;
+    if(temp > RNMX)
+      temp = RNMX;
+    return temp;
+  }
+
+  /*
+   * Returns a normally distributed deviate with zero mean and variance 1.
+   * Also looks like it's from "Numerical Recipes in C".
+   */
+  float
+  random::gasdev()
+  {
+    float fac,rsq,v1,v2;
+    d_iset = 1 - d_iset;
+    if(d_iset) {
+      do {
+        v1=2.0*ran1()-1.0;
+        v2=2.0*ran1()-1.0;
+        rsq=v1*v1+v2*v2;
+      } while(rsq >= 1.0 || rsq == 0.0);
+      fac= sqrt(-2.0*log(rsq)/rsq);
+      d_gset=v1*fac;
+      return v2*fac;
+    }
+    return d_gset;
+  }
+
+  /*
+   * Copied from The KC7WW / OH2BNS Channel Simulator
+   * FIXME Need to check how good this is at some point
+   */
+  float
+  random::laplacian()
+  {
+    float z = ran1();
+    if(z < 0.5)
+      return log(2.0 * z) / M_SQRT2;
+    else
+      return -log(2.0 * (1.0 - z)) / M_SQRT2;
+  }
+
+  /*
+   * Copied from The KC7WW / OH2BNS Channel Simulator
+   * FIXME Need to check how good this is at some point
+   */
+  // 5 => scratchy, 8 => Geiger
+  float
+  random::impulse(float factor = 5)
+  {
+    float z = -M_SQRT2 * log(ran1());
+    if(fabsf(z) <= factor)
+      return 0.0;
+    else
+      return z;
+  }
+
+  /*
+   * Complex rayleigh is really gaussian I and gaussian Q
+   * It can also be generated by real rayleigh magnitude and
+   * uniform random angle
+   * Adapted from The KC7WW / OH2BNS Channel Simulator
+   * FIXME Need to check how good this is at some point
+   */
+  gr_complex
+  random::rayleigh_complex()
+  {
+    return gr_complex(gasdev(),gasdev());
+  }
+
+  /*   Other option
+       mag = rayleigh();
+       ang = 2.0 * M_PI * RNG();
+       *Rx = rxx * cos(z);
+       *Iy = rxx * sin(z);
+       */
+
+  float
+  random::rayleigh()
+  {
+    return sqrt(-2.0 * log(ran1()));
+  }
+
+} /* namespace gr */