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Class template discard_block_engine

boost::random::discard_block_engine

Synopsis

// In header: <boost/random/discard_block.hpp>

template<typename UniformRandomNumberGenerator,  p,  r> 
class discard_block_engine {
public:
  // types
  typedef UniformRandomNumberGenerator ;  
  typedef base_type::result_type       ;

  // construct/copy/destruct
  ();
  (const base_type &);
  (base_type &&);
  ();
  template<typename SeedSeq> (SeedSeq &);
  template<typename It> (It &, It);

  // public member functions
  void ();
  void ();
  template<typename SeedSeq> void (SeedSeq &);
  template<typename It> void (It &, It);
  const base_type & () ;
  result_type ();
  void (boost::uintmax_t);
  template<typename It> void (It, It);

  // public static functions
  constexpr result_type ();
  constexpr result_type ();

  // friend functions
  template<typename CharT, typename Traits> 
    CharT, Traits > & 
    (CharT, Traits > &, 
               const discard_block_engine &);
  template<typename CharT, typename Traits> 
    CharT, Traits > & 
    (CharT, Traits > &, discard_block_engine &);
  bool (const discard_block_engine &, const discard_block_engine &);
  bool (const discard_block_engine &, const discard_block_engine &);

  // public data members
  static const  block_size;
  static const  used_block;
  static const bool has_fixed_range;
  static const  total_block;
  static const  returned_block;
};

Description

The class template discard_block_engine is a model of pseudo-random number generator . It modifies another generator by discarding parts of its output. Out of every block of p results, the first r will be returned and the rest discarded.

Requires: 0 < p <= r

discard_block_engine public construct/copy/destruct

  1. ();

    Uses the default seed for the base generator.

  2. (const base_type & rng);

    Constructs a new discard_block_engine with a copy of rng.

  3. (base_type && rng);

    Constructs a new discard_block_engine with rng.

  4. ( value);

    Creates a new discard_block_engine and seeds the underlying generator with value

  5. template<typename SeedSeq> (SeedSeq & seq);

    Creates a new discard_block_engine and seeds the underlying generator with seq

  6. template<typename It> (It & first, It last);

    Creates a new discard_block_engine and seeds the underlying generator with first and last.

discard_block_engine public member functions

  1. void ();

    default seeds the underlying generator.

  2. void ( s);

    Seeds the underlying generator with s.

  3. template<typename SeedSeq> void (SeedSeq & seq);

    Seeds the underlying generator with seq.

  4. template<typename It> void (It & first, It last);

    Seeds the underlying generator with first and last.

  5. const base_type & () ;

    Returns the underlying engine.

  6. result_type ();

    Returns the next value of the generator.

  7. void (boost::uintmax_t z);
  8. template<typename It> void (It first, It last);

discard_block_engine public static functions

  1. constexpr result_type ();

    Returns the smallest value that the generator can produce. This is the same as the minimum of the underlying generator.

  2. constexpr result_type ();

    Returns the largest value that the generator can produce. This is the same as the maximum of the underlying generator.

discard_block_engine friend functions

  1. template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > & os, 
                 const discard_block_engine & s);

    Writes a discard_block_engine to a std::ostream.

  2. template<typename CharT, typename Traits> 
      CharT, Traits > & 
      (CharT, Traits > & is, 
                 discard_block_engine & s);

    Reads a discard_block_engine from a std::istream.

  3. bool (const discard_block_engine & x, 
                    const discard_block_engine & y);

    Returns true if the two generators will produce identical sequences.

  4. bool (const discard_block_engine & x, 
                    const discard_block_engine & y);

    Returns true if the two generators will produce different sequences.


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