Class XorShift128PlusRandomGenerator
- All Implemented Interfaces:
RandomGenerator
By using the supplied jump()
method it is possible to generate non-overlapping long sequences
for parallel computations. This class provides also a split()
method to support recursive parallel computations, in the spirit of
SplittableRandom
.
Warning: before release 2.6.3, the split()
method
would not alter the state of the caller, and it would return instances initialized in the same
way if called multiple times. This was a major mistake in the implementation and it has been fixed,
but as a consequence the output of the caller after a call to split()
is
now different, and the result of split()
is initialized in a different way.
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Constructor Summary
ConstructorDescriptionDeprecated.Creates a new generator seeded usingUtil.randomSeed()
.XorShift128PlusRandomGenerator
(long seed) Deprecated.Creates a new generator using a given seed. -
Method Summary
Modifier and TypeMethodDescriptionvoid
jump()
Deprecated.The jump function for this generator.static void
Deprecated.boolean
Deprecated.void
nextBytes
(byte[] bytes) Deprecated.double
Deprecated.float
Deprecated.int
nextInt()
Deprecated.int
nextInt
(int n) Deprecated.long
nextLong()
Deprecated.long
nextLong
(long n) Deprecated.Returns a pseudorandom uniformly distributedlong
value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.void
setSeed
(long seed) Deprecated.Sets the seed of this generator.void
setState
(long[] state) Deprecated.Sets the state of this generator.split()
Deprecated.Returns a new instance that shares no mutable state with this instance.Methods inherited from class org.apache.commons.math3.random.AbstractRandomGenerator
clear, nextGaussian, setSeed, setSeed
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Constructor Details
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XorShift128PlusRandomGenerator
public XorShift128PlusRandomGenerator()Deprecated.Creates a new generator seeded usingUtil.randomSeed()
. -
XorShift128PlusRandomGenerator
public XorShift128PlusRandomGenerator(long seed) Deprecated.Creates a new generator using a given seed.- Parameters:
seed
- a seed for the generator.
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Method Details
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nextLong
public long nextLong()Deprecated.- Specified by:
nextLong
in interfaceRandomGenerator
- Overrides:
nextLong
in classAbstractRandomGenerator
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nextInt
public int nextInt()Deprecated.- Specified by:
nextInt
in interfaceRandomGenerator
- Overrides:
nextInt
in classAbstractRandomGenerator
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nextInt
public int nextInt(int n) Deprecated.- Specified by:
nextInt
in interfaceRandomGenerator
- Overrides:
nextInt
in classAbstractRandomGenerator
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nextLong
public long nextLong(long n) Deprecated.Returns a pseudorandom uniformly distributedlong
value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence. The algorithm used to generate the value guarantees that the result is uniform, provided that the sequence of 64-bit values produced by this generator is.- Parameters:
n
- the positive bound on the random number to be returned.- Returns:
- the next pseudorandom
long
value between0
(inclusive) andn
(exclusive).
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nextDouble
public double nextDouble()Deprecated.- Specified by:
nextDouble
in interfaceRandomGenerator
- Specified by:
nextDouble
in classAbstractRandomGenerator
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nextFloat
public float nextFloat()Deprecated.- Specified by:
nextFloat
in interfaceRandomGenerator
- Overrides:
nextFloat
in classAbstractRandomGenerator
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nextBoolean
public boolean nextBoolean()Deprecated.- Specified by:
nextBoolean
in interfaceRandomGenerator
- Overrides:
nextBoolean
in classAbstractRandomGenerator
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nextBytes
public void nextBytes(byte[] bytes) Deprecated.- Specified by:
nextBytes
in interfaceRandomGenerator
- Overrides:
nextBytes
in classAbstractRandomGenerator
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jump
public void jump()Deprecated.The jump function for this generator. It is equivalent to 264 calls tonextLong()
; it can be used to generate 264 non-overlapping subsequences for parallel computations. -
split
Deprecated.Returns a new instance that shares no mutable state with this instance. The sequence generated by the new instance depends deterministically from the state of this instance, but the probability that the sequence generated by this instance and by the new instance overlap is negligible.Warning: before release 2.6.3, this method would not alter the state of the caller, and it would return instances initialized in the same way if called multiple times. This was a major mistake in the implementation and it has been fixed, but as a consequence the output of this instance after a call to this method is now different, and the returned instance is initialized in a different way.
- Returns:
- the new instance.
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setSeed
public void setSeed(long seed) Deprecated.Sets the seed of this generator.The argument will be used to seed a
SplitMix64RandomGenerator
, whose output will in turn be used to seed this generator. This approach makes “warmup” unnecessary, and makes the probability of starting from a state with a large fraction of bits set to zero astronomically small.- Specified by:
setSeed
in interfaceRandomGenerator
- Specified by:
setSeed
in classAbstractRandomGenerator
- Parameters:
seed
- a seed for this generator.
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setState
public void setState(long[] state) Deprecated.Sets the state of this generator.The internal state of the generator will be reset, and the state array filled with the provided array.
- Parameters:
state
- an array of 2 longs; at least one must be nonzero.
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main
Deprecated.
-
XoRoShiRo128PlusRandomGenerator
instead.