std::discard_block_engine

 

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Pseudo-random number generation

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std::discard_block_engine

Member functions

discard_block_engine::discard_block_engine

discard_block_engine::seed

discard_block_engine::base

Generation

discard_block_engine::operator()

discard_block_engine::discard

Characteristics

discard_block_engine::min

discard_block_engine::max

Non-member functions

operator==operator!= (C++11)(C++11)(until C++20)

operator<<operator>> (C++11)(C++11)

 

Defined in header <random>
template<     class Engine,     std::size_t P, std::size_t R > class discard_block_engine;		(since C++11)

discard_block_engine is a pseudo-random number engine adaptor that discards a certain amount of data produced by the base engine. From each block of size P generated by the base engine, the adaptor keeps only R numbers, discarding the rest.

Template parameters

Engine	-	the type of the wrapped engine.
P	-	the size of a block. Expected that \(\small{P>0}\)P > 0.
R	-	the number of used numbers per block. Expected that \(\small{0<R\le P}\)0 < R ≤ P.
Type requirements
- Engine must meet the requirements of RandomNumberEngine.

Member types

Member type	Definition
result_type (C++11)	Engine::result_type

Member functions

(constructor) (C++11)	constructs the engine adaptor (public member function)
seed (C++11)	sets the state of the underlying engine (public member function)
base (C++11)	returns the underlying engine (public member function)
Generation
operator() (C++11)	advances the state of the underlying engine and returns the generated value (public member function)
discard (C++11)	advances the adaptor's state by a specified amount (public member function)
Characteristics
min [static] (C++11)	gets the smallest possible value in the output range of the underlying engine. (public static member function)
max [static] (C++11)	gets the largest possible value in the output range of the underlying engine. (public static member function)

Non-member functions

operator==operator!= (C++11)(C++11)(removed in C++20)	compares the internal states of the adaptors and underlying engines (function)
operator<<operator>> (C++11)	performs stream input and output on pseudo-random number engine adaptor (function)

Member constants

constexpr size_t block_size [static] (C++11)	the size of the block, P (public static member constant)
constexpr size_t used_block [static] (C++11)	the number of used numbers per block, R (public static member constant)