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Class template uniform_real_distribution

boost::random::uniform_real_distribution

Synopsis

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

template<typename RealType = double> 
class uniform_real_distribution {
public:
  // types
  typedef RealType input_type; 
  typedef RealType result_type;

  // member classes/structs/unions

  class param_type {
  public:
    // types
    typedef uniform_real_distribution distribution_type;

    // public member functions
    explicit param_type(RealType = 0.0, RealType = 1.0);
    RealType a() const;
    RealType b() const;

    // friend functions
    template<typename CharT, typename Traits> 
      std::basic_ostream< CharT, Traits > & 
      operator<<(std::basic_ostream< CharT, Traits > &, const param_type &);
    template<typename CharT, typename Traits> 
      std::basic_istream< CharT, Traits > & 
      operator>>(std::basic_istream< CharT, Traits > &, const param_type &);
    bool operator==(const param_type &, const param_type &);
    bool operator!=(const param_type &, const param_type &);
  };

  // public member functions
  explicit uniform_real_distribution(RealType = 0.0, RealType = 1.0);
  explicit uniform_real_distribution(const param_type &);
  RealType min() const;
  RealType max() const;
  RealType a() const;
  RealType b() const;
  param_type param() const;
  void param(const param_type &);
  void reset();
  template<typename Engine> result_type operator()(Engine &) const;
  template<typename Engine> 
    result_type operator()(Engine &, const param_type &) const;

  // friend functions
  template<typename CharT, typename Traits> 
    std::basic_ostream< CharT, Traits > & 
    operator<<(std::basic_ostream< CharT, Traits > &, 
               const uniform_real_distribution &);
  template<typename CharT, typename Traits> 
    std::basic_istream< CharT, Traits > & 
    operator>>(std::basic_istream< CharT, Traits > &, 
               const uniform_real_distribution &);
  bool operator==(const uniform_real_distribution &, 
                  const uniform_real_distribution &);
  bool operator!=(const uniform_real_distribution &, 
                  const uniform_real_distribution &);
};

Description

The class template uniform_real_distribution models a random distribution . On each invocation, it returns a random floating-point value uniformly distributed in the range [min..max).

uniform_real_distribution public member functions

  1. explicit uniform_real_distribution(RealType min = 0.0, RealType max = 1.0);

    Constructs a uniform_real_distribution. min and max are the parameters of the distribution.

    Requires: min < max

  2. explicit uniform_real_distribution(const param_type & param);

    Constructs a uniform_real_distribution from its parameters.

  3. RealType min() const;

    Returns the minimum value of the distribution

  4. RealType max() const;

    Returns the maximum value of the distribution

  5. RealType a() const;

    Returns the minimum value of the distribution

  6. RealType b() const;

    Returns the maximum value of the distribution

  7. param_type param() const;

    Returns the parameters of the distribution.

  8. void param(const param_type & param);

    Sets the parameters of the distribution.

  9. void reset();

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

  10. template<typename Engine> result_type operator()(Engine & eng) const;

    Returns a value uniformly distributed in the range [min, max).

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

    Returns a value uniformly distributed in the range [param.a(), param.b()).

uniform_real_distribution friend functions

  1. template<typename CharT, typename Traits> 
      std::basic_ostream< CharT, Traits > & 
      operator<<(std::basic_ostream< CharT, Traits > & os, 
                 const uniform_real_distribution & ud);

    Writes the distribution to a std::ostream.

  2. template<typename CharT, typename Traits> 
      std::basic_istream< CharT, Traits > & 
      operator>>(std::basic_istream< CharT, Traits > & is, 
                 const uniform_real_distribution & ud);

    Reads the distribution from a std::istream.

  3. bool operator==(const uniform_real_distribution & lhs, 
                    const uniform_real_distribution & rhs);

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

  4. bool operator!=(const uniform_real_distribution & lhs, 
                    const uniform_real_distribution & rhs);

    Returns true if the two distributions may produce different sequences of values given equal generators.


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