[rand.dist.bern] (original) (raw)

29 Numerics library [numerics]

29.5 Random number generation [rand]

29.5.9 Random number distribution class templates [rand.dist]

29.5.9.3 Bernoulli distributions [rand.dist.bern]

29.5.9.3.1 Class bernoulli_distribution [rand.dist.bern.bernoulli]

A bernoulli_distribution random number distribution produces bool values bdistributed according to the discrete probability function in Formula 29.4.

namespace std { class bernoulli_distribution { public: using result_type = bool;using param_type = unspecified; bernoulli_distribution() : bernoulli_distribution(0.5) {} explicit bernoulli_distribution(double p);explicit bernoulli_distribution(const param_type& parm);void reset();friend bool operator==(const bernoulli_distribution& x, const bernoulli_distribution& y);template<class URBG> result_type operator()(URBG& g);template<class URBG> result_type operator()(URBG& g, const param_type& parm);double p() const; param_type param() const;void param(const param_type& parm); result_type min() const; result_type max() const;template<class charT, class traits> friend basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const bernoulli_distribution& x);template<class charT, class traits> friend basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& is, bernoulli_distribution& x);};}

explicit bernoulli_distribution(double p);

Preconditions: 0 ≤ p ≤ 1.

Remarks: p corresponds to the parameter of the distribution.

Returns: The value of the p parameter with which the object was constructed.

29.5.9.3.2 Class template binomial_distribution [rand.dist.bern.bin]

A binomial_distribution random number distribution produces integer values i ≥ 0distributed according to the discrete probability function in Formula 29.5.

namespace std { template<class IntType = int> class binomial_distribution { public: using result_type = IntType;using param_type = unspecified; binomial_distribution() : binomial_distribution(1) {} explicit binomial_distribution(IntType t, double p = 0.5);explicit binomial_distribution(const param_type& parm);void reset();friend bool operator==(const binomial_distribution& x, const binomial_distribution& y);template<class URBG> result_type operator()(URBG& g);template<class URBG> result_type operator()(URBG& g, const param_type& parm); IntType t() const;double p() const; param_type param() const;void param(const param_type& parm); result_type min() const; result_type max() const;template<class charT, class traits> friend basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const binomial_distribution& x);template<class charT, class traits> friend basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& is, binomial_distribution& x);};}

explicit binomial_distribution(IntType t, double p = 0.5);

Preconditions: 0 ≤ p ≤ 1 and 0 ≤ t.

Remarks: t and p correspond to the respective parameters of the distribution.

Returns: The value of the t parameter with which the object was constructed.

Returns: The value of the p parameter with which the object was constructed.

29.5.9.3.3 Class template geometric_distribution [rand.dist.bern.geo]

A geometric_distribution random number distribution produces integer values i ≥ 0distributed according to the discrete probability function in Formula 29.6.

namespace std { template<class IntType = int> class geometric_distribution { public: using result_type = IntType;using param_type = unspecified; geometric_distribution() : geometric_distribution(0.5) {} explicit geometric_distribution(double p);explicit geometric_distribution(const param_type& parm);void reset();friend bool operator==(const geometric_distribution& x, const geometric_distribution& y);template<class URBG> result_type operator()(URBG& g);template<class URBG> result_type operator()(URBG& g, const param_type& parm);double p() const; param_type param() const;void param(const param_type& parm); result_type min() const; result_type max() const;template<class charT, class traits> friend basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const geometric_distribution& x);template<class charT, class traits> friend basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& is, geometric_distribution& x);};}

explicit geometric_distribution(double p);

Remarks: p corresponds to the parameter of the distribution.

Returns: The value of the p parameter with which the object was constructed.

29.5.9.3.4 Class template negative_binomial_distribution [rand.dist.bern.negbin]

A negative_binomial_distribution random number distribution produces random integers i ≥ 0distributed according to the discrete probability function in Formula 29.7.

[Note 1:

This implies that P(i | k,p) is undefined when p == 1.

— _end note_]

namespace std { template<class IntType = int> class negative_binomial_distribution { public: using result_type = IntType;using param_type = unspecified; negative_binomial_distribution() : negative_binomial_distribution(1) {} explicit negative_binomial_distribution(IntType k, double p = 0.5);explicit negative_binomial_distribution(const param_type& parm);void reset();friend bool operator==(const negative_binomial_distribution& x,const negative_binomial_distribution& y);template<class URBG> result_type operator()(URBG& g);template<class URBG> result_type operator()(URBG& g, const param_type& parm); IntType k() const;double p() const; param_type param() const;void param(const param_type& parm); result_type min() const; result_type max() const;template<class charT, class traits> friend basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const negative_binomial_distribution& x);template<class charT, class traits> friend basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& is, negative_binomial_distribution& x);};}

explicit negative_binomial_distribution(IntType k, double p = 0.5);

Remarks: k and p correspond to the respective parameters of the distribution.

Returns: The value of the k parameter with which the object was constructed.

Returns: The value of the p parameter with which the object was constructed.