Class XoRoShiRo128PlusPlus
- All Implemented Interfaces:
RandomLongSource
,JumpableUniformRandomProvider
,LongJumpableUniformRandomProvider
,RestorableUniformRandomProvider
,UniformRandomProvider
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:
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate static final long[]
The coefficients for the jump function.private static final long[]
The coefficients for the long jump function.Fields inherited from class org.apache.commons.rng.core.source64.AbstractXoRoShiRo128
state0, state1
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Constructor Summary
ConstructorsModifierConstructorDescriptionXoRoShiRo128PlusPlus
(long[] seed) Creates a new instance.XoRoShiRo128PlusPlus
(long seed0, long seed1) Creates a new instance using a 2 element seed.protected
Creates a copy instance. -
Method Summary
Modifier and TypeMethodDescriptionprotected XoRoShiRo128PlusPlus
copy()
Create a copy.jump()
Creates a copy of the UniformRandomProvider and then advances the state of the current instance.longJump()
Creates a copy of the JumpableUniformRandomProvider and then advances the state of the current instance.long
next()
protected long
Use the current state to compute the next output from the generator.Methods inherited from class org.apache.commons.rng.core.source64.AbstractXoRoShiRo128
getStateInternal, performJump, setStateInternal
Methods inherited from class org.apache.commons.rng.core.source64.LongProvider
nextBoolean, nextInt, nextLong, resetCachedState
Methods inherited from class org.apache.commons.rng.core.BaseProvider
checkIndex, checkStateSize, composeStateInternal, extendSeed, extendSeed, fillState, fillState, restoreState, saveState, splitStateInternal, toString
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.JumpableUniformRandomProvider
jumps, jumps
Methods inherited from interface org.apache.commons.rng.LongJumpableUniformRandomProvider
longJumps, longJumps
Methods inherited from interface org.apache.commons.rng.UniformRandomProvider
doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextBoolean, nextBytes, nextBytes, nextDouble, nextDouble, nextDouble, nextFloat, nextFloat, nextFloat, nextInt, nextInt, nextInt, nextLong, nextLong, nextLong
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Field Details
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JUMP_COEFFICIENTS
private static final long[] JUMP_COEFFICIENTSThe coefficients for the jump function. -
LONG_JUMP_COEFFICIENTS
private static final long[] LONG_JUMP_COEFFICIENTSThe coefficients for the long jump function.
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Constructor Details
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XoRoShiRo128PlusPlus
public XoRoShiRo128PlusPlus(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.
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XoRoShiRo128PlusPlus
public XoRoShiRo128PlusPlus(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.
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XoRoShiRo128PlusPlus
Creates a copy instance.- Parameters:
source
- Source to copy.
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Method Details
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next
public long next()- Specified by:
next
in interfaceRandomLongSource
- Overrides:
next
in classAbstractXoRoShiRo128
- Returns:
- the next random value.
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nextOutput
protected long nextOutput()Use the current state to compute the next output from the generator. The output function shall vary with respect to different generators. This method is called fromAbstractXoRoShiRo128.next()
before the current state is updated.- Specified by:
nextOutput
in classAbstractXoRoShiRo128
- Returns:
- the next output
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jump
Creates a copy of the UniformRandomProvider and then advances the state of the current instance. The copy is returned.The current state will be advanced in a single operation by the equivalent of a number of sequential calls to a method that updates the state of the provider. The size of the jump is implementation dependent.
Repeat invocations of this method will create a series of generators that are uniformly spaced at intervals of the output sequence. Each generator provides non-overlapping output for the length of the jump for use in parallel computations.
The jump size is the equivalent of 264 calls to
nextLong()
. It can provide up to 264 non-overlapping subsequences.- Specified by:
jump
in interfaceJumpableUniformRandomProvider
- Overrides:
jump
in classAbstractXoRoShiRo128
- Returns:
- A copy of the current state.
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longJump
Creates a copy of the JumpableUniformRandomProvider and then advances the state of the current instance. The copy is returned.The current state will be advanced in a single operation by the equivalent of a number of sequential calls to a method that updates the state of the provider. The size of the long jump is implementation dependent.
Repeat invocations of this method will create a series of generators that are uniformly spaced at intervals of the output sequence. Each generator provides non-overlapping output for the length of the long jump for use in parallel computations.
The returned copy may be jumped
m / n
times before overlap with the current instance wherem
is the long jump length andn
is the jump length of theJumpableUniformRandomProvider.jump()
method.The jump size is the equivalent of 296 calls to
nextLong()
. It can provide up to 232 non-overlapping subsequences of length 296; each subsequence can provide up to 232 non-overlapping subsequences of length 264 using theAbstractXoRoShiRo128.jump()
method.- Specified by:
longJump
in interfaceLongJumpableUniformRandomProvider
- Overrides:
longJump
in classAbstractXoRoShiRo128
- Returns:
- A copy of the current state.
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copy
Create a copy.- Specified by:
copy
in classAbstractXoRoShiRo128
- Returns:
- the copy
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