math.rng

Class SplitMix64

java.lang.Object

math.rng.AbstractRng64

math.rng.SplitMix64

All Implemented Interfaces:

PseudoRandom, PseudoRandomStream, SplittablePseudoRandom

public class SplitMix64
extends AbstractRng64
implements SplittablePseudoRandom

64-bit SplitMix-type pseudo random generator suggested by Guy Steele, Doug Lea, Christine Flood (2014). This implementation is basically the same algorithm as used in SplittableRandom but it employs different mixing functions to (hopefully) protect better against the possible problems with weak gamma values reported in Steele (2017). Performance should be about the same as for SplittableRandom.

This generator has a period of 2⁶⁴.

This generator is 1-dimensionally equidistributed.

Field Summary

Fields inherited from class math.rng.AbstractRng64

DOUBLE_NORM, FLOAT_NORM, nextGaussian, unused

Constructor Summary

Constructors

Modifier	Constructor and Description
	SplitMix64()
	SplitMix64(long seed)
	SplitMix64(long[] seed)
protected	SplitMix64(long seed, long gamma)

Method Summary

Modifier and Type	Method and Description
static SplittablePseudoRandom	getDefault()
int	nextInt()
long	nextLong()
SplitMix64	split() Constructs and returns a new SplittablePseudoRandom instance that shares no mutable state with the current instance.

Methods inherited from class math.rng.AbstractRng64

beta, beta, cauchy, cauchy, chiSquare, chiSquare, doubles, doubles, doubles, doubles, exponential, exponential, gamma, gamma, getAlgorithm, getSeed, ints, ints, ints, ints, logNormal, logNormal, longs, longs, longs, longs, next, nextBoolean, nextBytes, nextDouble, nextDouble, nextDoubles, nextFloat, nextFloat, nextGaussian, nextGaussian, nextInt, nextInt, nextLong, nextLong, nextLongs, normal, normal, saveSeed, saveSeed, studentT, studentT, weibull, weibull

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface math.rng.PseudoRandom

getAlgorithm, getSeed, next, nextBoolean, nextBytes, nextDouble, nextDouble, nextDoubles, nextFloat, nextFloat, nextGaussian, nextGaussian, nextInt, nextInt, nextLong, nextLong, nextLongs

Methods inherited from interface math.rng.PseudoRandomStream

beta, beta, cauchy, cauchy, chiSquare, chiSquare, doubles, doubles, doubles, doubles, exponential, exponential, gamma, gamma, ints, ints, ints, ints, logNormal, logNormal, longs, longs, longs, longs, normal, normal, studentT, studentT, weibull, weibull

Constructor Detail

SplitMix64

public SplitMix64()

SplitMix64

public SplitMix64(long seed)

SplitMix64

public SplitMix64(long[] seed)

SplitMix64

protected SplitMix64(long seed,
                     long gamma)

Method Detail

nextLong

public final long nextLong()

Specified by:

nextLong in interface PseudoRandom

Specified by:

nextLong in class AbstractRng64

nextInt

public final int nextInt()

Specified by:

nextInt in interface PseudoRandom

Overrides:

nextInt in class AbstractRng64

split

public SplitMix64 split()

Description copied from interface: SplittablePseudoRandom

Constructs and returns a new SplittablePseudoRandom instance that shares no mutable state with the current instance. However, with very high probability, the values collectively generated by the two instances have the same statistical properties as if the same quantity of values were generated by a single thread using a single SplittablePseudoRandom instance. Instances of SplittablePseudoRandom are not thread-safe. They are designed to be split, not shared, across threads.

Specified by:

split in interface SplittablePseudoRandom

Returns:

a new SplittablePseudoRandom instance that shares no mutable state with the current instance

getDefault

public static SplittablePseudoRandom getDefault()