Class AbstractXoRoShiRo128
- All Implemented Interfaces:
RandomLongSource
,JumpableUniformRandomProvider
,LongJumpableUniformRandomProvider
,RestorableUniformRandomProvider
,UniformRandomProvider
- Direct Known Subclasses:
XoRoShiRo128Plus
,XoRoShiRo128PlusPlus
,XoRoShiRo128StarStar
- 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.private static final int
Size of the state vector.protected long
State 0 of the generator.protected long
State 1 of the generator. -
Constructor Summary
ConstructorsModifierConstructorDescription(package private)
AbstractXoRoShiRo128
(long[] seed) Creates a new instance.(package private)
AbstractXoRoShiRo128
(long seed0, long seed1) Creates a new instance using a 2 element seed.protected
Creates a copy instance. -
Method Summary
Modifier and TypeMethodDescriptionprotected abstract AbstractXoRoShiRo128
copy()
Create a copy.protected byte[]
Creates a snapshot of the RNG state.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 abstract long
Use the current state to compute the next output from the generator.(package private) final void
performJump
(long[] jumpCoefficients) Perform the jump to advance the generator state.private void
setState
(long[] state) Copies the state from the array into the generator state.protected void
setStateInternal
(byte[] s) Resets the RNG to the givenstate
.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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SEED_SIZE
private static final int SEED_SIZESize of the state vector.- See Also:
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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. -
state0
protected long state0State 0 of the generator. -
state1
protected long state1State 1 of the generator.
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Constructor Details
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AbstractXoRoShiRo128
AbstractXoRoShiRo128(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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AbstractXoRoShiRo128
AbstractXoRoShiRo128(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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AbstractXoRoShiRo128
Creates a copy instance.- Parameters:
source
- Source to copy.
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Method Details
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setState
private void setState(long[] state) Copies the state from the array into the generator state.- Parameters:
state
- the new state
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getStateInternal
protected byte[] getStateInternal()Creates a snapshot of the RNG state.- Overrides:
getStateInternal
in classLongProvider
- Returns:
- the internal state.
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setStateInternal
protected void setStateInternal(byte[] s) Resets the RNG to the givenstate
.- Overrides:
setStateInternal
in classLongProvider
- Parameters:
s
- State (previously obtained by a call toBaseProvider.getStateInternal()
).- See Also:
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next
public long next()- Specified by:
next
in interfaceRandomLongSource
- Returns:
- the next random value.
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nextOutput
protected abstract 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 fromnext()
before the current state is updated.- 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
- 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 thejump()
method.- Specified by:
longJump
in interfaceLongJumpableUniformRandomProvider
- Returns:
- A copy of the current state.
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copy
Create a copy.- Returns:
- the copy
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performJump
final void performJump(long[] jumpCoefficients) Perform the jump to advance the generator state. Resets the cached state of the generator.- Parameters:
jumpCoefficients
- Jump coefficients.
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