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Class template exponential_distribution

boost::random::exponential_distribution

Synopsis

// In header: <boost/random/exponential_distribution.hpp>

template<typename RealType> 
class exponential_distribution {
public:
  // types
  typedef RealType ; 
  typedef RealType ;

  // member classes/structs/unions

  class param_type {
  public:
    // types
    typedef exponential_distribution ;

    // public member functions
    (RealType = );
    RealType () ;

    // friend functions
    template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > &, const  param_type &);
    template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > &, const  param_type &);
    bool (const  param_type &, const  param_type &);
    bool (const  param_type &, const  param_type &);
  };

  // public member functions
  (RealType = );
  (const  param_type &);
  RealType () ;
  RealType () ;
  RealType () ;
  param_type () ;
  void (const  param_type &);
  void ();
  template<typename Engine> result_type (Engine &) ;
  template<typename Engine> 
    result_type (Engine &, const  param_type &) ;

  // friend functions
  template<typename CharT, typename Traits> 
    CharT, Traits > & 
    (CharT, Traits > &, 
               const  exponential_distribution &);
  template<typename CharT, typename Traits> 
    CharT, Traits > & 
    (CharT, Traits > &, 
               const  exponential_distribution &);
  bool (const  exponential_distribution &, 
                  const  exponential_distribution &);
  bool (const  exponential_distribution &, 
                  const  exponential_distribution &);
};

Description

The exponential distribution is a model of random distribution with a single parameter lambda.

It has

The implementation uses the "ziggurat" algorithm, as described in

"The Ziggurat Method for Generating Random Variables", George Marsaglia and Wai Wan Tsang, Journal of Statistical Software Volume 5, Number 8 (2000), 1-7.

exponential_distribution public member functions

  1. (RealType lambda = );

    Constructs an exponential_distribution with a given lambda.

    Requires: lambda > 0

  2. (const  param_type & param);

    Constructs an exponential_distribution from its parameters

  3. RealType () ;

    Returns the lambda parameter of the distribution.

  4. RealType () ;

    Returns the smallest value that the distribution can produce.

  5. RealType () ;

    Returns the largest value that the distribution can produce.

  6. param_type () ;

    Returns the parameters of the distribution.

  7. void (const  param_type & param);

    Sets the parameters of the distribution.

  8. void ();

    Effects: Subsequent uses of the distribution do not depend on values produced by any engine prior to invoking reset.

  9. template<typename Engine> result_type (Engine & eng) ;

    Returns a random variate distributed according to the exponential distribution.

  10. template<typename Engine> 
      result_type (Engine & eng, const  param_type & param) ;

    Returns a random variate distributed according to the exponential distribution with parameters specified by param.

exponential_distribution friend functions

  1. template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > & os, 
                 const  exponential_distribution & ed);

    Writes the distribution to a std::ostream.

  2. template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > & is, 
                 const  exponential_distribution & ed);

    Reads the distribution from a std::istream.

  3. bool (const  exponential_distribution & lhs, 
                    const  exponential_distribution & rhs);

    Returns true iff the two distributions will produce identical sequences of values given equal generators.

  4. bool (const  exponential_distribution & lhs, 
                    const  exponential_distribution & rhs);

    Returns true iff the two distributions will produce different sequences of values given equal generators.


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