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## Class param_type

boost::random::beta_distribution::param_type

## Synopsis

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

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

      // public member functions
      explicit param_type(RealType = 1.0, RealType = 1.0);
      RealType alpha() const;
      RealType beta() 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 &);
    };

## Description

### `param_type` public member functions

1.     explicit param_type(RealType alpha = 1.0, RealType beta = 1.0);

   Constructs a `param_type` from the "alpha" and "beta" parameters of the distribution.

   Requires: alpha > 0, beta > 0

2.     RealType alpha() const;

   Returns the "alpha" parameter of the distribtuion.

3.     RealType beta() const;

   Returns the "beta" parameter of the distribution.

### `param_type` friend functions

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

   Writes a `param_type` to a `std::ostream`.

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

   Reads a `param_type` from a `std::istream`.

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

   Returns true if the two sets of parameters are the same.

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

   Returns true if the two sets of parameters are the different.