std::linear_congruential_engine
<random>
class UIntType,
UIntType a,
UIntType c,
UIntType m
linear_congruential_engine
is a random number engine based on Linear congruential generator (LCG).
Contents
[edit] Template parameters
When m is not zero, if a >= m or c >= m is true, the program is ill-formed.
[edit] Generator properties
The size of the states of linear_congruential_engine
is 1, each of them consists of a single integer.
The actual modulus \(\scriptsize m_0\)m0 is defined as follows:
- If m is not zero, \(\scriptsize m_0\)m0 is m.
- If m is zero, \(\scriptsize m_0\)m0 is the value of std::numeric_limits <result_type>::max() plus 1 (which means \(\scriptsize m_0\)m0 need not be representable as
result_type
).
The transition algorithm of linear_congruential_engine
is \(\scriptsize TA(x_i) = (a \cdot x_i + c)\mod m_0\)TA(xi) = (a·xi+c) mod m0.
The generation algorithm of linear_congruential_engine
is \(\scriptsize GA(x_i) = (a \cdot x_i + c)\mod m_0\)GA(xi) = (a·xi+c) mod m0.
The pseudo-random number generated with the current state is also the successor state.
[edit] Predefined specializations
The following specializations define the random number engine with two commonly used parameter sets:
<random>
minstd_rand0
(C++11)
std::linear_congruential_engine<std::uint_fast32_t,
16807, 0, 2147483647>Discovered in 1969 by Lewis, Goodman and Miller, adopted as "Minimal standard" in 1988 by Park and Miller[edit]
minstd_rand
(C++11)
std::linear_congruential_engine<std::uint_fast32_t,
48271, 0, 2147483647>
Newer "Minimum standard", recommended by Park, Miller, and Stockmeyer in 1993[edit]
[edit] Nested types
result_type
UIntType
[edit] Data members
(public static member constant)
(public static member constant)
(public static member constant)
(public static member constant)
[edit] Member functions
Construction and Seeding
Generation
Characteristics
(public static member function) [edit]
[edit] Non-member functions
(function) [edit]
[edit] Example
Reason: no example