29 Numerics library [numerics]

29.6 Random number generation [rand]

29.6.8 Random number distribution class templates [rand.dist]

29.6.8.3 Bernoulli distributions [rand.dist.bern]

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

A bernoulli_­distribution random number distribution produces bool values b distributed according to the discrete probability function

class bernoulli_distribution {
public:
  // types
  using result_type = bool;
  using param_type  = unspecified;

  // constructors and reset functions
  explicit bernoulli_distribution(double p = 0.5);
  explicit bernoulli_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
  double p() const;
  param_type param() const;
  void param(const param_type& parm);
  result_type min() const;
  result_type max() const;
};

explicit bernoulli_distribution(double p = 0.5);

Requires: .

Effects: Constructs a bernoulli_­distribution object; p corresponds to the parameter of the distribution.

double p() const;

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

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

A binomial_­distribution random number distribution produces integer values distributed according to the discrete probability function

template<class IntType = int>
  class binomial_distribution {
  public:
    // types
    using result_type = IntType;
    using param_type  = unspecified;

    // constructors and reset functions
    explicit binomial_distribution(IntType t = 1, double p = 0.5);
    explicit binomial_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
    IntType t() const;
    double p() const;
    param_type param() const;
    void param(const param_type& parm);
    result_type min() const;
    result_type max() const;
  };

explicit binomial_distribution(IntType t = 1, double p = 0.5);

Requires: and .

Effects: Constructs a binomial_­distribution object; t and p correspond to the respective parameters of the distribution.

IntType t() const;

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

double p() const;

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

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

A geometric_­distribution random number distribution produces integer values distributed according to the discrete probability function

template<class IntType = int>
  class geometric_distribution {
  public:
    // types
    using result_type = IntType;
    using param_type  = unspecified;

    // constructors and reset functions
    explicit geometric_distribution(double p = 0.5);
    explicit geometric_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
    double p() const;
    param_type param() const;
    void param(const param_type& parm);
    result_type min() const;
    result_type max() const;
  };

explicit geometric_distribution(double p = 0.5);

Requires: .

Effects: Constructs a geometric_­distribution object; p corresponds to the parameter of the distribution.

double p() const;

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

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

A negative_­binomial_­distribution random number distribution produces random integers distributed according to the discrete probability function

[Note: This implies that is undefined when p == 1. end note]

template<class IntType = int>
  class negative_binomial_distribution {
  public:
    // types
    using result_type = IntType;
    using param_type  = unspecified;

    // constructor and reset functions
    explicit negative_binomial_distribution(IntType k = 1, double p = 0.5);
    explicit negative_binomial_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
    IntType k() const;
    double p() const;
    param_type param() const;
    void param(const param_type& parm);
    result_type min() const;
    result_type max() const;
  };

explicit negative_binomial_distribution(IntType k = 1, double p = 0.5);

Requires: and .

Effects: Constructs a negative_­binomial_­distribution object; k and p correspond to the respective parameters of the distribution.

IntType k() const;

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

double p() const;

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