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## Class template triangle_distribution

boost::random::triangle_distribution

## Synopsis

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

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

      // member classes/structs/unions

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

        // construct/copy/destruct
        explicit param_type(RealType = 0.0, RealType = 0.5, RealType = 1.0);

        // public member functions
        RealType a() const;
        RealType b() const;
        RealType c() 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 triangle_distribution(RealType = 0.0, RealType = 0.5,
                                     RealType = 1.0);
      explicit triangle_distribution(const param_type &);

      // public member functions
      result_type a() const;
      result_type b() const;
      result_type c() const;
      RealType min() const;
      RealType max() const;
      param_type param() const;
      void param(const param_type &);
      void reset();
      template<typename Engine> result_type operator()(Engine &);
      template<typename Engine>
        result_type operator()(Engine &, const param_type &);

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

## Description

Instantiations of `triangle_distribution` model a random distribution . A `triangle_distribution` has three parameters, `a`, `b`, and `c`, which are the smallest, the most probable and the largest values of the distribution respectively.

### `triangle_distribution` public construct/copy/destruct

1.     explicit triangle_distribution(RealType a = 0.0, RealType b = 0.5,
                                      RealType c = 1.0);

   Constructs a ``triangle_distribution`` with the parameters `a`, `b`, and `c`.

   Preconditions: a <= b <= c.

2.     explicit triangle_distribution(const param_type & param);

   Constructs a ``triangle_distribution`` from its parameters.

### `triangle_distribution` public member functions

1.     result_type a() const;

   Returns the `a` parameter of the distribution

2.     result_type b() const;

   Returns the `b` parameter of the distribution

3.     result_type c() const;

   Returns the `c` parameter of the distribution

4.     RealType min() const;

   Returns the smallest value that the distribution can produce.

5.     RealType max() const;

   Returns the largest value that the distribution can produce.

6.     param_type param() const;

   Returns the parameters of the distribution.

7.     void param(const param_type & param);

   Sets the parameters of the distribution.

8.     void reset();

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

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

   Returns a random variate distributed according to the triangle distribution.

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

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

### `triangle_distribution` friend functions

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

   Writes 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 triangle_distribution & td);

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

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

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

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

   Returns true if the two distributions may produce different sequences of values given equal generators.