Adding boost random support and system libs

Boost/boost/random/poisson_distribution.hpp

@@ -0,0 +1,116 @@
+/* boost random/poisson_distribution.hpp header file
+ *
+ * Copyright Jens Maurer 2002
+ * Distributed under the Boost Software License, Version 1.0. (See
+ * accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * See http://www.boost.org for most recent version including documentation.
+ *
+ * $Id: poisson_distribution.hpp 60755 2010-03-22 00:45:06Z steven_watanabe $
+ *
+ */
+
+#ifndef BOOST_RANDOM_POISSON_DISTRIBUTION_HPP
+#define BOOST_RANDOM_POISSON_DISTRIBUTION_HPP
+
+#include <boost/config/no_tr1/cmath.hpp>
+#include <cassert>
+#include <iostream>
+#include <boost/limits.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/random/detail/config.hpp>
+
+namespace boost {
+
+// Knuth
+
+/**
+ * An instantiation of the class template @c poisson_distribution is a
+ * model of \random_distribution.  The poisson distribution has
+ * \f$p(i) = \frac{e^{-\lambda}\lambda^i}{i!}\f$
+ */
+template<class IntType = int, class RealType = double>
+class poisson_distribution
+{
+public:
+  typedef RealType input_type;
+  typedef IntType result_type;
+
+  /**
+   * Constructs a @c poisson_distribution with the parameter @c mean.
+   *
+   * Requires: mean > 0
+   */
+  explicit poisson_distribution(const RealType& mean_arg = RealType(1))
+    : _mean(mean_arg)
+  {
+#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
+    // MSVC fails BOOST_STATIC_ASSERT with std::numeric_limits at class scope
+    BOOST_STATIC_ASSERT(std::numeric_limits<IntType>::is_integer);
+    BOOST_STATIC_ASSERT(!std::numeric_limits<RealType>::is_integer);
+#endif
+
+    assert(_mean > RealType(0));
+    init();
+  }
+
+  // compiler-generated copy ctor and assignment operator are fine
+
+  /**
+   * Returns: the "mean" parameter of the distribution.
+   */
+  RealType mean() const { return _mean; }
+  void reset() { }
+
+  template<class Engine>
+  result_type operator()(Engine& eng)
+  {
+    // TODO: This is O(_mean), but it should be O(log(_mean)) for large _mean
+    RealType product = RealType(1);
+    for(result_type m = 0; ; ++m) {
+      product *= eng();
+      if(product <= _exp_mean)
+        return m;
+    }
+  }
+
+#ifndef BOOST_RANDOM_NO_STREAM_OPERATORS
+  template<class CharT, class Traits>
+  friend std::basic_ostream<CharT,Traits>&
+  operator<<(std::basic_ostream<CharT,Traits>& os, const poisson_distribution& pd)
+  {
+    os << pd._mean;
+    return os;
+  }
+
+  template<class CharT, class Traits>
+  friend std::basic_istream<CharT,Traits>&
+  operator>>(std::basic_istream<CharT,Traits>& is, poisson_distribution& pd)
+  {
+    is >> std::ws >> pd._mean;
+    pd.init();
+    return is;
+  }
+#endif
+
+private:
+  /// \cond hide_private_members
+  void init()
+  {
+#ifndef BOOST_NO_STDC_NAMESPACE
+    // allow for Koenig lookup
+    using std::exp;
+#endif
+    _exp_mean = exp(-_mean);
+  }
+  /// \endcond
+
+  RealType _mean;
+  // some precomputed data from the parameters
+  RealType _exp_mean;
+};
+
+} // namespace boost
+
+#endif // BOOST_RANDOM_POISSON_DISTRIBUTION_HPP