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## Class template bernoulli_distribution

boost::random::bernoulli_distribution

## Synopsis

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

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

      // member classes/structs/unions

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

        // construct/copy/destruct
        explicit param_type(RealType = 0.5);

        // public member functions
        RealType p() 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 bernoulli_distribution(const RealType & = 0.5);
      explicit bernoulli_distribution(const param_type &);

      // public member functions
      RealType p() const;
      bool min() const;
      bool max() const;
      param_type param() const;
      void param(const param_type &);
      void reset();
      template<typename Engine> bool operator()(Engine &) const;
      template<typename Engine>
        bool 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 bernoulli_distribution &);
      template<typename CharT, typename Traits>
        friend std::basic_istream< CharT, Traits > &
        operator>>(std::basic_istream< CharT, Traits > &,
                   const bernoulli_distribution &);
      friend bool operator==(const bernoulli_distribution &,
                             const bernoulli_distribution &);
      friend bool operator!=(const bernoulli_distribution &,
                             const bernoulli_distribution &);
    };

## Description

Instantiations of class template bernoulli_distribution model a random distribution . Such a random distribution produces bool values distributed with probabilities P(true) = p and P(false) = 1-p. p is the parameter of the distribution.

### `bernoulli_distribution` public construct/copy/destruct

1.     explicit bernoulli_distribution(const RealType & p = 0.5);

   Constructs a `bernoulli_distribution` object. p is the parameter of the distribution.

   Requires: 0 <= p <= 1

2.     explicit bernoulli_distribution(const param_type & param);

   Constructs `bernoulli_distribution` from its parameters

### `bernoulli_distribution` public member functions

1.     RealType p() const;

   Returns: The "p" parameter of the distribution.

2.     bool min() const;

   Returns the smallest value that the distribution can produce.

3.     bool max() const;

   Returns the largest value that the distribution can produce.

4.     param_type param() const;

   Returns the parameters of the distribution.

5.     void param(const param_type & param);

   Sets the parameters of the distribution.

6.     void reset();

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

7.     template<typename Engine> bool operator()(Engine & eng) const;

   Returns: a random variate distributed according to the `bernoulli_distribution` .

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

   Returns: a random variate distributed according to the `bernoulli_distribution` with parameters specified by param.

### `bernoulli_distribution` friend functions

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

   Writes the parameters of 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 bernoulli_distribution & bd);

   Reads the parameters of the distribution from a `std::istream`.

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

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

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

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