std::mersenne_twister_engine

C++

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Named requirements

Language support library

Concepts library (C++20)

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Technical Specifications

Numerics library

Common mathematical functions

Special mathematical functions

Floating-point environment (C++11)

Complex numbers

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Pseudo-random number generation

Compile-time rational arithmetic (C++11)

Numeric algorithms

gcd (C++17)

lcm (C++17)

Generic numeric operations

iota (C++11)

accumulate

inner_product

adjacent_difference

partial_sum

reduce (C++17)

transform_reduce (C++17)

inclusive_scan (C++17)

exclusive_scan (C++17)

transform_inclusive_scan (C++17)

transform_exclusive_scan (C++17)

Bit operations

bit_cast (C++20)

ispow2 (C++20)

ceil2 (C++20)

floor2 (C++20)

log2p1 (C++20)

Pseudo-random number generation

Uniform random bit generators

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)

Distributions

Uniform distributions

uniform_int_distribution (C++11)

uniform_real_distribution (C++11)

generate_canonical (C++11)

Bernoulli distributions

bernoulli_distribution (C++11)

binomial_distribution (C++11)

negative_binomial_distribution (C++11)

geometric_distribution (C++11)

Poisson distributions

poisson_distribution (C++11)

exponential_distribution (C++11)

gamma_distribution (C++11)

weibull_distribution (C++11)

extreme_value_distribution (C++11)

Normal distributions

normal_distribution (C++11)

lognormal_distribution (C++11)

chi_squared_distribution (C++11)

cauchy_distribution (C++11)

fisher_f_distribution (C++11)

student_t_distribution (C++11)

Sampling distributions

discrete_distribution (C++11)

piecewise_constant_distribution (C++11)

piecewise_linear_distribution (C++11)

Seed Sequences

seed_seq (C++11)

C library

rand

srand

RAND_MAX

std::mersenne_twister_engine

Member functions

mersenne_twister_engine::mersenne_twister_engine

mersenne_twister_engine::seed

Generation

mersenne_twister_engine::operator()

mersenne_twister_engine::discard

Characteristics

mersenne_twister_engine::min

mersenne_twister_engine::max

Non-member functions

operator==operator!=

operator<<operator>>

Defined in header <random>
template< class UIntType, size_t w, size_t n, size_t m, size_t r, UIntType a, size_t u, UIntType d, size_t s, UIntType b, size_t t, UIntType c, size_t l, UIntType f > class mersenne_twister_engine;		(since C++11)

mersenne_twister_engine is a random number engine based on Mersenne Twister algorithm. It produces high quality unsigned integer random numbers of type UIntType on the interval [0, 2w
-1].

The following type aliases define the random number engine with two commonly used parameter sets:

Defined in header <random>
Type	Definition
mt19937	std::mersenne_twister_engine<std::uint_fast32_t, 32, 624, 397, 31, 0x9908b0df, 11, 0xffffffff, 7, 0x9d2c5680, 15, 0xefc60000, 18, 1812433253> 32-bit Mersenne Twister by Matsumoto and Nishimura, 1998
mt19937_64	std::mersenne_twister_engine<std::uint_fast64_t, 64, 312, 156, 31, 0xb5026f5aa96619e9, 29, 0x5555555555555555, 17, 0x71d67fffeda60000, 37, 0xfff7eee000000000, 43, 6364136223846793005> 64-bit Mersenne Twister by Matsumoto and Nishimura, 2000

Member types

Member type	Definition
result_type	The integral type generated by the engine. Results are undefined if this is not an unsigned integral type.

Member functions

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

Non-member functions

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

Member objects

constexpr size_t word_size [static]	the template parameter w, determines the range of values generated by the engine. (public static member constant)
constexpr size_t state_size [static]	the template parameter n. The engine state is n values of UIntType (public static member constant)
constexpr size_t shift_size [static]	the template parameter m (public static member constant)
constexpr size_t mask_bits [static]	the template parameter r, also known as the twist value. (public static member constant)
constexpr UIntType xor_mask [static]	the template parameter a, the conditional xor-mask. (public static member constant)
constexpr size_t tempering_u [static]	the template parameter u, first component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr UIntType tempering_d [static]	the template parameter d, second component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr size_t tempering_s [static]	the template parameter s, third component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr UIntType tempering_b [static]	the template parameter b, fourth component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr size_t tempering_t [static]	the template parameter t, fifth component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr UIntType tempering_c [static]	the template parameter c, sixth component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr size_t tempering_l [static]	the template parameter l, seventh component of the bit-scrambling (tempering) matrix (public static member constant)
constexpr UIntType initialization_multiplier [static]	the template parameter f (public static member constant)
constexpr UIntType default_seed [static]	the constant value 5489u (public static member constant)

Notes

The 10000th consecutive invocation of a default-contructed std::mt19937 is required to produce the value 4123659995.

The 10000th consecutive invocation of a default-contructed std::mt19937_64 is required to produce the value 9981545732273789042