Package org.apache.commons.rng.core.source64

Class XoRoShiRo128StarStar

java.lang.Object

org.apache.commons.rng.core.BaseProvider

org.apache.commons.rng.core.source64.LongProvider

org.apache.commons.rng.core.source64.XoRoShiRo128StarStar

All Implemented Interfaces:

RandomLongSource, RestorableUniformRandomProvider, UniformRandomProvider

public class XoRoShiRo128StarStar
extends LongProvider

A fast all-purpose 64-bit generator.

This is a member of the Xor-Shift-Rotate family of generators. Memory footprint is 128 bits and the period is 2¹²⁸-1. Speed is expected to be similar to XoShiRo256StarStar.

Since:

1.3

See Also:

Original source code, xorshiro / xoroshiro generators

Field Summary

Fields

Modifier and Type	Field	Description
protected long	state0	State 0 of the generator.
protected long	state1	State 1 of the generator.

Constructor Summary

Constructors

Constructor	Description
XoRoShiRo128StarStar(long[] seed)	Creates a new instance.
XoRoShiRo128StarStar(long seed0, long seed1)	Creates a new instance using a 2 element seed.

Method Summary

Modifier and Type	Method	Description
protected byte[]	getStateInternal()	Creates a snapshot of the RNG state.
long	next()
protected void	setStateInternal(byte[] s)	Resets the RNG to the given state.

Methods inherited from class org.apache.commons.rng.core.source64.LongProvider

nextBoolean, nextBytes, nextBytes, nextDouble, nextFloat, nextInt, nextLong

Methods inherited from class org.apache.commons.rng.core.BaseProvider

checkIndex, checkStateSize, composeStateInternal, fillState, fillState, nextInt, nextLong, restoreState, saveState, splitStateInternal, toString

Methods inherited from class java.lang.Object

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

Field Details

state0

protected long state0

State 0 of the generator.

state1

protected long state1

State 1 of the generator.

Constructor Details

XoRoShiRo128StarStar

public XoRoShiRo128StarStar(long[] seed)

Creates a new instance.

Parameters:

seed - Initial seed. If the length is larger than 2, only the first 2 elements will be used; if smaller, the remaining elements will be automatically set. A seed containing all zeros will create a non-functional generator.

XoRoShiRo128StarStar

public XoRoShiRo128StarStar(long seed0, long seed1)

Creates a new instance using a 2 element seed. A seed containing all zeros will create a non-functional generator.

Parameters:

seed0 - Initial seed element 0.

seed1 - Initial seed element 1.

Method Details

next

public long next()

Returns:

the next random value.

getStateInternal

protected byte[] getStateInternal()

Creates a snapshot of the RNG state.

Overrides:

getStateInternal in class LongProvider

Returns:

the internal state.

setStateInternal

protected void setStateInternal(byte[] s)

Resets the RNG to the given state.

Overrides:

setStateInternal in class LongProvider

Parameters:

s - State (previously obtained by a call to BaseProvider.getStateInternal()).

See Also:

BaseProvider.checkStateSize(byte[],int)