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## Class template fisher_f_distribution

boost::random::fisher_f_distribution

## Synopsis

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

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

      // member classes/structs/unions

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

        // construct/copy/destruct
        explicit param_type(RealType = 1.0, RealType = 1.0);

        // public member functions
        RealType m() const;
        RealType n() 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 fisher_f_distribution(RealType = 1.0, RealType = 1.0);
      explicit fisher_f_distribution(const param_type &);

      // public member functions
      template<typename URNG> RealType operator()(URNG &);
      template<typename URNG>
        RealType operator()(URNG &, const param_type &) const;
      RealType m() const;
      RealType n() const;
      RealType min() const;
      RealType max() const;
      param_type param() const;
      void param(const param_type &);
      void reset();

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

## Description

The Fisher F distribution is a real valued distribution with two parameters m and n.

It has .

### `fisher_f_distribution` public construct/copy/destruct

1.     explicit fisher_f_distribution(RealType m = 1.0, RealType n = 1.0);

   Constructs a ``fisher_f_distribution`` from its "m" and "n" parameters.

   Requires: m > 0 and n > 0

2.     explicit fisher_f_distribution(const param_type & param);

   Constructs an ``fisher_f_distribution`` from its parameters.

### `fisher_f_distribution` public member functions

1.     template<typename URNG> RealType operator()(URNG & urng);

   Returns a random variate distributed according to the F distribution.

2.     template<typename URNG>
         RealType operator()(URNG & urng, const param_type & param) const;

   Returns a random variate distributed according to the F distribution with parameters specified by `param`.

3.     RealType m() const;

   Returns the "m" parameter of the distribution.

4.     RealType n() const;

   Returns the "n" parameter of the distribution.

5.     RealType min() const;

   Returns the smallest value that the distribution can produce.

6.     RealType max() const;

   Returns the largest value that the distribution can produce.

7.     param_type param() const;

   Returns the parameters of the distribution.

8.     void param(const param_type & param);

   Sets the parameters of the distribution.

9.     void reset();

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

### `fisher_f_distribution` friend functions

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

   Writes an ``fisher_f_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 fisher_f_distribution & fd);

   Reads an ``fisher_f_distribution`` from a `std::istream`.

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

   Returns true if the two instances of ``fisher_f_distribution`` will return identical sequences of values given equal generators.

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

   Returns true if the two instances of ``fisher_f_distribution`` will return different sequences of values given equal generators.