...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::random::beta_distribution
// 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; // construct/copy/destruct explicit param_type(RealType = 1.0, RealType = 1.0); // public member functions RealType alpha() const; RealType beta() 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 beta_distribution(RealType = 1.0, RealType = 1.0); explicit beta_distribution(const param_type &); // public member functions 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> friend std::basic_ostream< CharT, Traits > & operator<<(std::basic_ostream< CharT, Traits > &, const beta_distribution &); template<typename CharT, typename Traits> friend std::basic_istream< CharT, Traits > & operator>>(std::basic_istream< CharT, Traits > &, const beta_distribution &); friend bool operator==(const beta_distribution &, const beta_distribution &); friend bool operator!=(const beta_distribution &, const beta_distribution &); };
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
construct/copy/destructexplicit beta_distribution(RealType alpha = 1.0, RealType beta = 1.0);
Constructs an
from its "alpha" and "beta" parameters.beta_distribution
Requires: alpha > 0, beta > 0
explicit beta_distribution(const param_type & param);
Constructs an
from its parameters. beta_distribution
beta_distribution
public member functionstemplate<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 functionstemplate<typename CharT, typename Traits> friend std::basic_ostream< CharT, Traits > & operator<<(std::basic_ostream< CharT, Traits > & os, const beta_distribution & wd);
Writes an
to a beta_distribution
std::ostream
.
template<typename CharT, typename Traits> friend std::basic_istream< CharT, Traits > & operator>>(std::basic_istream< CharT, Traits > & is, const beta_distribution & wd);
Reads an
from a beta_distribution
std::istream
.
friend bool operator==(const beta_distribution & lhs, const beta_distribution & rhs);
Returns true if the two instances of
will return identical sequences of values given equal generators. beta_distribution
friend bool operator!=(const beta_distribution & lhs, const beta_distribution & rhs);
Returns true if the two instances of
will return different sequences of values given equal generators. beta_distribution