26 Numerics library [numerics]

26.6 Random number generation [rand]

26.6.8 Random number distribution class templates [rand.dist]

26.6.8.3 Bernoulli distributions [rand.dist.bern]

26.6.8.3.4 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
    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();

    // 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, 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.