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## Class param_type

boost::random::non_central_chi_squared_distribution::param_type

## Synopsis

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

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

      // construct/copy/destruct
      explicit param_type(RealType = 1, RealType = 1);

      // public member functions
      RealType k() const;
      RealType lambda() 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 &);
    };

## Description

### `param_type` public construct/copy/destruct

1.     explicit param_type(RealType k = 1, RealType lambda = 1);

   Constructs the parameters of a `non_central_chi_squared_distribution`. `k` and `lambda` are the parameter of the distribution.

   Requires: k > 0 && lambda > 0

### `param_type` public member functions

1.     RealType k() const;

   Returns the `k` parameter of the distribution

2.     RealType lambda() const;

   Returns the `lambda` parameter of the distribution

### `param_type` friend functions

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

   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 param_type & param);

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

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

   Returns true if the parameters have the same values.

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

   Returns true if the parameters have different values.