XorshiftEngine

The Xorshift family of generators, developed by George Marsaglia (2003), offer high-quality random number generation with minimal storage requirements and computational cost. They are therefore highly suitable for use in low-memory environments or slower processors. The current implementation supports Xorshift random number generation with a 32-bit datatype only.

The total number of bits used to store the internal state is reflected in the statistical quality of the resulting generator. The table below lists the number of bits used by each Xorshift generator (which must be a multiple of the datatype size) and the corresponding period of the generator.

$(TEXTWITHCOMMAS Number of $(D bits) used (2nd parameter of $(D_PARAM XorshiftEngine)) and corresponding period of the resulting generator)
bits	period
32	2^32 - 1
64	2^64 - 1
96	2^96 - 1
128	2^128 - 1
160	2^160 - 1
192	2^192 - 2^32

@safe final

class XorshiftEngine (

UIntType

UIntType bits

UIntType a

UIntType b

UIntType c

) if (

isUnsigned!UIntType

) {

enum bool isUniformRandom;

enum UIntType min;

enum UIntType max;

this();

this(UIntType x0);

void seed(UIntType x0);

enum bool empty;

UIntType front();

void popFront();

typeof(this) save();

bool opEquals(Object rhs);

}

Constructors

this this(): Constructs an XorshiftEngine using the default seed configuration.
this this(UIntType x0): Constructs an XorshiftEngine generator seeded with x0.

Members

Functions

front UIntType front(): Returns the current pseudo-random value.
opEquals bool opEquals(Object rhs): Compares against rhs for equality.
popFront void popFront(): Advances the pseudo-random sequence.
save typeof(this) save(): Captures a range state.
seed void seed(UIntType x0): (Re)seeds the generator with x0.

Variables

empty enum bool empty;: Always false (random number generators are infinite ranges).
isUniformRandom enum bool isUniformRandom;: Mark this as a Rng
max enum UIntType max;: Largest generated value.
min enum UIntType min;: Smallest generated value (0).

XorshiftEngine

Constructors

Members

Functions

Variables

Meta

Source