random: Get rid of uniform_distribution (non-portable).

* src/misc/random.cc, src/misc/random.hh,
src/tgbaalgos/randomgraph.cc, src/tgbatest/randaut.test,
src/tgbatest/randomize.test, src/tgbatest/readsave.test,
src/ltlvisit/simplify.cc, src/tgbaalgos/randomize.cc,
src/graph/graph.hh, src/tgbatest/randpsl.test: here.

src/misc/random.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2012, 2013, 2014 Laboratoire de Recherche et
+// Copyright (C) 2011, 2012, 2013, 2014, 2015 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 // Copyright (C) 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -22,6 +22,7 @@
 
 #include "config.h"
 #include "random.hh"
+#include <random>
 
 namespace spot
 {
@@ -36,28 +37,96 @@ namespace spot
   double
   drand()
   {
-    return
-      std::generate_canonical<double,
-			      std::numeric_limits<double>::digits>(gen);
+    return  gen() / (1.0 + gen.max());
   }
 
   int
   mrand(int max)
   {
-    std::uniform_int_distribution<> dis(0, max - 1);
-    return dis(gen);
+    return static_cast<int>(max * drand());
   }
 
   int
   rrand(int min, int max)
   {
-    std::uniform_int_distribution<> dis(min, max);
-    return dis(gen);
+    return min + static_cast<int>((max - min + 1) * drand());
+  }
+
+  double
+  nrand()
+  {
+    const double r = drand();
+
+    const double lim = 1.e-20;
+    if (r < lim)
+      return -1./lim;
+    if (r > 1.0 - lim)
+      return 1./lim;
+
+    double t;
+    if (r < 0.5)
+      t = sqrt(-2.0 * log(r));
+    else
+      t = sqrt(-2.0 * log(1.0 - r));
+
+    const double p0 = 0.322232431088;
+    const double p1 = 1.0;
+    const double p2 = 0.342242088547;
+    const double p3 = 0.204231210245e-1;
+    const double p4 = 0.453642210148e-4;
+    const double q0 = 0.099348462606;
+    const double q1 = 0.588581570495;
+    const double q2 = 0.531103462366;
+    const double q3 = 0.103537752850;
+    const double q4 = 0.385607006340e-2;
+    const double p = p0 + t * (p1 + t * (p2 + t * (p3 + t * p4)));
+    const double q = q0 + t * (q1 + t * (q2 + t * (q3 + t * q4)));
+
+    if (r < 0.5)
+      return (p / q) - t;
+    else
+      return t - (p / q);
+  }
+
+  double
+  bmrand()
+  {
+    static double next;
+    static bool has_next = false;
+
+    if (has_next)
+      {
+	has_next = false;
+	return next;
+      }
+
+    double x;
+    double y;
+    double r;
+    do
+      {
+	x = 2.0 * drand() - 1.0;
+	y = 2.0 * drand() - 1.0;
+	r = x * x + y * y;
+      }
+    while (r >= 1.0 || r == 0.0);
+    r = sqrt(-2 * log(r) / r);
+    next = y * r;
+    has_next = true;
+    return x * r;
   }
 
   int
-  barand::rand()
+  prand(double p)
   {
-    return (*this)(gen);
+    double s = 0.0;
+    long x = 0;
+
+    while (s < p)
+      {
+	s -= log(1.0 - drand());
+	++x;
+      }
+    return x - 1;
   }
 }

src/misc/random.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2013 Laboratoire de Recherche et Développement
+// Copyright (C) 2015 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 // Copyright (C) 2004  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -24,7 +24,8 @@
 # define SPOT_MISC_RANDOM_HH
 
 # include "common.hh"
-# include <random>
+# include <cmath>
+# include <vector>
 
 namespace spot
 {
@@ -55,18 +56,86 @@ namespace spot
   /// \see mrand, rrand, srand
   SPOT_API double drand();
 
+  /// \brief Compute a pseudo-random double value
+  /// following a standard normal distribution.  (Odeh & Evans)
+  ///
+  /// This uses a polynomial approximation of the inverse cumulated
+  /// density function from Odeh & Evans, Journal of Applied
+  /// Statistics, 1974, vol 23, pp 96-97.
+  SPOT_API double nrand();
+
+  /// \brief Compute a pseudo-random double value
+  /// following a standard normal distribution.  (Box-Muller)
+  ///
+  /// This uses the polar form of the Box-Muller transform
+  /// to generate random values.
+  SPOT_API double bmrand();
+
   /// \brief Compute pseudo-random integer value between 0
   /// and \a n included, following a binomial distribution
   /// for probability \a p.
-  class SPOT_API barand : protected std::binomial_distribution<>
+  ///
+  /// \a gen must be a random function computing a pseudo-random
+  /// double value following a standard normal distribution.
+  /// Use nrand() or bmrand().
+  ///
+  /// Usually approximating a binomial distribution using a normal
+  /// distribution and is accurate only if <code>n*p</code> and
+  /// <code>n*(1-p)</code> are greater than 5.
+  template<double (*gen)()>
+  class barand
   {
   public:
-    barand(int n, double p) : binomial_distribution(n, p)
+    barand(int n, double p)
+      : n_(n), m_(n * p), s_(sqrt(n * p * (1 - p)))
     {
     }
 
-    int rand();
+    int
+    rand() const
+    {
+      int res;
+
+      for (;;)
+	{
+	  double x = gen() * s_ + m_;
+	  if (x < 0.0)
+	    continue;
+	  res = static_cast<int> (x);
+          if (res <= n_)
+	    break;
+        }
+      return res;
+    }
+  protected:
+    const int n_;
+    const double m_;
+    const double s_;
   };
+
+  /// \brief Return a pseudo-random positive integer value
+  /// following a Poisson distribution with parameter \a p.
+  ///
+  /// \pre <code>p > 0</code>
+  SPOT_API int prand(double p);
+
+  /// \brief Shuffle the container using mrand function above.
+  /// This allows to get rid off shuffle or random_shuffle that use
+  /// uniform_distribution and RandomIterator that are not portables.
+  template<class iterator_type>
+  SPOT_API void mrandom_shuffle(iterator_type&& first, iterator_type&& last)
+  {
+    auto d = std::distance(first, last);
+    if (d > 1)
+      {
+	for (--last; first < last; ++first, --d)
+	  {
+	    auto i = mrand(d);
+	    std::swap(*first, *(first + i));
+	  }
+      }
+  }
+  /// @}
 }
 
 #endif // SPOT_MISC_RANDOM_HH