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Class template uniform_int_distribution

boost::random::uniform_int_distribution

Synopsis

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

template<typename IntType = int> 
class uniform_int_distribution {
public:
  // types
  typedef IntType input_type; 
  typedef IntType result_type;

  // member classes/structs/unions

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

    // construct/copy/destruct
    explicit param_type(IntType = 0, 
                        IntType = (std::numeric_limits< IntType >::max)());

    // public member functions
    IntType a() const;
    IntType b() const;

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

  // construct/copy/destruct
  explicit uniform_int_distribution(IntType = 0, 
                                    IntType = (std::numeric_limits< IntType >::max)());
  explicit uniform_int_distribution(const param_type &);

  // public member functions
  IntType min() const;
  IntType max() const;
  IntType a() const;
  IntType 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> 
    friend std::basic_ostream< CharT, Traits > & 
    operator<<(std::basic_ostream< CharT, Traits > &, 
               const uniform_int_distribution &);
  template<typename CharT, typename Traits> 
    friend std::basic_istream< CharT, Traits > & 
    operator>>(std::basic_istream< CharT, Traits > &, 
               const uniform_int_distribution &);
  friend bool operator==(const uniform_int_distribution &, 
                         const uniform_int_distribution &);
  friend bool operator!=(const uniform_int_distribution &, 
                         const uniform_int_distribution &);
};

Description

The class template uniform_int_distribution models a random distribution . On each invocation, it returns a random integer value uniformly distributed in the set of integers {min, min+1, min+2, ..., max}.

The template parameter IntType shall denote an integer-like value type.

uniform_int_distribution public construct/copy/destruct

  1. explicit uniform_int_distribution(IntType min = 0, 
                                      IntType max = (std::numeric_limits< IntType >::max)());

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

    Requires: min <= max

  2. explicit uniform_int_distribution(const param_type & param);

    Constructs a uniform_int_distribution from its parameters.

uniform_int_distribution public member functions

  1. IntType min() const;

    Returns the minimum value of the distribution

  2. IntType max() const;

    Returns the maximum value of the distribution

  3. IntType a() const;

    Returns the minimum value of the distribution

  4. IntType b() const;

    Returns the maximum value of the distribution

  5. param_type param() const;

    Returns the parameters of the distribution.

  6. void param(const param_type & param);

    Sets the parameters of the distribution.

  7. void reset();

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

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

    Returns an integer uniformly distributed in the range [min, max].

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

    Returns an integer uniformly distributed in the range [param.a(), param.b()].

uniform_int_distribution friend functions

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

    Writes the distribution to a std::ostream.

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

    Reads the distribution from a std::istream.

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

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

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

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


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