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regarded and expertly designed C++ library projects in the
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— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::random::exponential_distribution
// In header: <boost/random/exponential_distribution.hpp> template<typename RealType = double> class exponential_distribution { public: // types typedef RealType input_type; typedef RealType result_type; // member classes/structs/unions class param_type { public: // types typedef exponential_distribution distribution_type; // public member functions 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 &); // public data members __pad0__; }; // construct/copy/destruct explicit exponential_distribution(RealType = 1.0); explicit exponential_distribution(const param_type &); // public member functions RealType lambda() 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 &) const; template<typename Engine> result_type operator()(Engine &, const param_type &) const; // friend functions template<typename CharT, typename Traits> friend std::basic_ostream< CharT, Traits > & operator<<(std::basic_ostream< CharT, Traits > &, const exponential_distribution &); template<typename CharT, typename Traits> friend std::basic_istream< CharT, Traits > & operator>>(std::basic_istream< CharT, Traits > &, const exponential_distribution &); friend bool operator==(const exponential_distribution &, const exponential_distribution &); friend bool operator!=(const exponential_distribution &, const exponential_distribution &); };
The exponential distribution is a model of random distribution with a single parameter lambda.
It has
exponential_distribution
public
construct/copy/destructexplicit exponential_distribution(RealType lambda = 1.0);
Constructs an exponential_distribution
with a given lambda.
Requires: lambda > 0
explicit exponential_distribution(const param_type & param);
Constructs an exponential_distribution
from its parameters
exponential_distribution
public member functionsRealType lambda() const;
Returns the lambda 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.
template<typename Engine> result_type operator()(Engine & eng) const;
Returns a random variate distributed according to the exponential distribution.
template<typename Engine> result_type operator()(Engine & eng, const param_type & param) const;
Returns a random variate distributed according to the exponential distribution with parameters specified by param.
exponential_distribution
friend functionstemplate<typename CharT, typename Traits> friend std::basic_ostream< CharT, Traits > & operator<<(std::basic_ostream< CharT, Traits > & os, const exponential_distribution & ed);
Writes the distribution to a std::ostream.
template<typename CharT, typename Traits> friend std::basic_istream< CharT, Traits > & operator>>(std::basic_istream< CharT, Traits > & is, const exponential_distribution & ed);
Reads the distribution from a std::istream.
friend bool operator==(const exponential_distribution & lhs, const exponential_distribution & rhs);
Returns true iff the two distributions will produce identical sequences of values given equal generators.
friend bool operator!=(const exponential_distribution & lhs, const exponential_distribution & rhs);
Returns true iff the two distributions will produce different sequences of values given equal generators.