Class template beta_distribution

boost::random::beta_distribution

Synopsis

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

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

  // member classes/structs/unions

  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 &);
  };

  // public member functions
  explicit beta_distribution(RealType = 1.0, RealType = 1.0);
  explicit beta_distribution(const param_type &);
  template<typename URNG> RealType operator()(URNG &) const;
  template<typename URNG> 
    RealType operator()(URNG &, const param_type &) const;
  RealType alpha() const;
  RealType beta() 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> 
    std::basic_ostream< CharT, Traits > & 
    operator<<(std::basic_ostream< CharT, Traits > &, 
               const beta_distribution &);
  template<typename CharT, typename Traits> 
    std::basic_istream< CharT, Traits > & 
    operator>>(std::basic_istream< CharT, Traits > &, 
               const beta_distribution &);
  bool operator==(const beta_distribution &, const beta_distribution &);
  bool operator!=(const beta_distribution &, const beta_distribution &);
};

Description

The beta distribution is a real-valued distribution which produces values in the range [0, 1]. It has two parameters, alpha and beta.

It has .

`beta_distribution` public member functions

```
explicit beta_distribution(RealType alpha = 1.0, RealType beta = 1.0);
```
Constructs an beta_distribution from its "alpha" and "beta" parameters.

Requires: alpha > 0, beta > 0

explicit beta_distribution(const param_type & param);

Constructs an beta_distribution from its parameters.

```
template<typename URNG> RealType operator()(URNG & urng) const;
```
Returns a random variate distributed according to the beta distribution.
```
template<typename URNG> 
  RealType operator()(URNG & urng, const param_type & param) const;
```
Returns a random variate distributed accordint to the beta distribution with parameters specified by param.
```
RealType alpha() const;
```
Returns the "alpha" parameter of the distribution.
```
RealType beta() const;
```
Returns the "beta" parameter of the distribution.
```
RealType min() const;
```
Returns the smallest value that the distribution can produce.
```
RealType max() const;
```
Returns the largest value that the distribution can produce.
```
param_type param() const;
```
Returns the parameters of the distribution.
```
void param(const param_type & param);
```
Sets the parameters of the distribution.
```
void reset();
```
Effects: Subsequent uses of the distribution do not depend on values produced by any engine prior to invoking reset.

`beta_distribution` friend functions

template<typename CharT, typename Traits> 
  std::basic_ostream< CharT, Traits > & 
  operator<<(std::basic_ostream< CharT, Traits > & os, 
             const beta_distribution & wd);

Writes an beta_distribution to a std::ostream.

template<typename CharT, typename Traits> 
  std::basic_istream< CharT, Traits > & 
  operator>>(std::basic_istream< CharT, Traits > & is, 
             const beta_distribution & wd);

Reads an beta_distribution from a std::istream.

```
bool operator==(const beta_distribution & lhs, const beta_distribution & rhs);
```
Returns true if the two instances of beta_distribution will return identical sequences of values given equal generators.
```
bool operator!=(const beta_distribution & lhs, const beta_distribution & rhs);
```
Returns true if the two instances of beta_distribution will return different sequences of values given equal generators.

Boost C++ Libraries

Class template beta_distribution

Synopsis

Description

beta_distribution public member functions

beta_distribution friend functions

`beta_distribution` public member functions

`beta_distribution` friend functions