29 Numerics library [numerics]

29.6 Random number generation [rand]

29.6.8 Random number distribution class templates [rand.dist] Bernoulli distributions [rand.dist.bern] Class template geometric_­distribution [rand.dist.bern.geo]

A geometric_­distribution random number distribution produces integer values i0 distributed according to the discrete probability function


template<class IntType = int>
  class geometric_distribution {
    // 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: 0<p<1.

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.