26 Numerics library [numerics]

26.6 Random number generation [rand]

26.6.9 Random number distribution class templates [rand.dist] Normal distributions [rand.dist.norm] Class template chi_­squared_­distribution [rand.dist.norm.chisq]

A chi_­squared_­distribution random number distribution produces random numbers distributed according to the probability density function
template<class RealType = double> class chi_squared_distribution { public: // types using result_type = RealType; using param_type = unspecified; // constructor and reset functions chi_squared_distribution() : chi_squared_distribution(1.0) {} explicit chi_squared_distribution(RealType n); explicit chi_squared_distribution(const param_type& parm); void reset(); // generating functions template<class URBG> result_type operator()(URBG& g); template<class URBG> result_type operator()(URBG& g, const param_type& parm); // property functions RealType n() const; param_type param() const; void param(const param_type& parm); result_type min() const; result_type max() const; };
explicit chi_squared_distribution(RealType n);
Preconditions: .
Remarks: n corresponds to the parameter of the distribution.
RealType n() const;
Returns: The value of the n parameter with which the object was constructed.