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## Class template bernoulli_distribution

boost::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;

      // construct/copy/destruct
      bernoulli_distribution(const RealType & = RealType(0.5));

      // public member functions
      RealType p() const;
      void reset();
      template<typename Engine> result_type operator()(Engine &);

      // 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 > &,
                   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.     bernoulli_distribution(const RealType & p_arg = RealType(0.5));

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

   Requires: 0 <= p <= 1

### `bernoulli_distribution` public member functions

1.     RealType p() const;

   Returns: The "p" parameter of the distribution.

2.     void reset();

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

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

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

### `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,
                    bernoulli_distribution & bd);

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