std::discard_block_engine

C++

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Technical Specifications

Numerics library

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Pseudo-random number generation

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UniformRandomBitGenerator (C++20)

Engines and engine adaptors

linear_congruential_engine (C++11)

mersenne_twister_engine (C++11)

subtract_with_carry_engine (C++11)

discard_block_engine (C++11)

independent_bits_engine (C++11)

shuffle_order_engine (C++11)

Non-deterministic generator

random_device (C++11)

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poisson_distribution (C++11)

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normal_distribution (C++11)

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discrete_distribution (C++11)

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piecewise_linear_distribution (C++11)

Seed Sequences

seed_seq (C++11)

C library

rand

srand

RAND_MAX

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!=

operator<<operator>>

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

discard_block_engine is a pseudo-random number generator 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. Must be greater than 0.
R	-	the number of used numbers per block. Must be greater than 0 and not greater than P
Type requirements
- Engine must meet the requirements of RandomNumberEngine.

Member types

Member type	Definition
result_type	Engine::result_type

Member functions

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

Non-member functions

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

Member objects

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