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

Class XoRoShiRo1024PlusPlus

java.lang.Object

org.apache.commons.rng.core.BaseProvider

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

org.apache.commons.rng.core.source64.XoRoShiRo1024PlusPlus

All Implemented Interfaces:

RandomLongSource, JumpableUniformRandomProvider, LongJumpableUniformRandomProvider, RestorableUniformRandomProvider, UniformRandomProvider

public class XoRoShiRo1024PlusPlus
extends LongProvider

A large-state all-purpose 64-bit generator.

This is a member of the Xor-Shift-Rotate family of generators. Memory footprint is 1024 bits and the period is 2¹⁰²⁴-1.

Note: This can be used as a replacement for XorShift1024Star.

Since:

1.3

See Also:

Original source code, xorshiro / xoroshiro generators

Constructor Summary

Constructors

Modifier	Constructor	Description
	XoRoShiRo1024PlusPlus(long[] seed)	Creates a new instance.
protected	XoRoShiRo1024PlusPlus(XoRoShiRo1024PlusPlus source)	Creates a copy instance.

Method Summary

Modifier and Type	Method	Description
protected XoRoShiRo1024PlusPlus	copy()	Create a copy.
protected byte[]	getStateInternal()	Creates a snapshot of the RNG state.
UniformRandomProvider	jump()
JumpableUniformRandomProvider	longJump()
long	next()
protected void	setStateInternal(byte[] s)	Resets the RNG to the given state.
protected long	transform(long s0, long s15)	Transform the two consecutive 64-bit states of the generator to a 64-bit output.

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

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

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.rng.UniformRandomProvider

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

Constructor Detail

XoRoShiRo1024PlusPlus

public XoRoShiRo1024PlusPlus(long[] seed)

Creates a new instance.

Parameters:

seed - Initial seed. If the length is larger than 16, only the first 16 elements will be used; if smaller, the remaining elements will be automatically set. A seed containing all zeros will create a non-functional generator.

XoRoShiRo1024PlusPlus

protected XoRoShiRo1024PlusPlus(XoRoShiRo1024PlusPlus source)

Creates a copy instance.

Parameters:

source - Source to copy.

Method Detail

transform

protected long transform(long s0,
                         long s15)

Transform the two consecutive 64-bit states of the generator to a 64-bit output. The transformation function shall vary with respect to different generators.

Parameters:

s0 - The current state.

s15 - The previous state.

Returns:

the output

copy

protected XoRoShiRo1024PlusPlus copy()

Create a copy.

Returns:

the copy

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)

next

public long next()

Specified by:

next in interface RandomLongSource

Returns:

the next random value.

jump

public UniformRandomProvider jump()

The jump size is the equivalent of 2⁵¹² calls to nextLong(). It can provide up to 2⁵¹² non-overlapping subsequences.

Specified by:

jump in interface JumpableUniformRandomProvider

longJump

public JumpableUniformRandomProvider longJump()

The jump size is the equivalent of 2⁷⁶⁸ calls to nextLong(). It can provide up to 2²⁵⁶ non-overlapping subsequences of length 2⁷⁶⁸; each subsequence can provide up to 2²⁵⁶ non-overlapping subsequences of length 2⁵¹²using the jump() method.

Specified by:

longJump in interface LongJumpableUniformRandomProvider