Package org.hipparchus.random
Class Well44497b
java.lang.Object
org.hipparchus.random.AbstractWell
org.hipparchus.random.Well44497b
- All Implemented Interfaces:
Serializable,RandomGenerator
This class implements the WELL44497b pseudo-random number generator
from François Panneton, Pierre L'Ecuyer and Makoto Matsumoto.
This generator is described in a paper by François Panneton, Pierre L'Ecuyer and Makoto Matsumoto Improved Long-Period Generators Based on Linear Recurrences Modulo 2 ACM Transactions on Mathematical Software, 32, 1 (2006). The errata for the paper are in wellrng-errata.txt.
- See Also:
-
Nested Class Summary
Nested classes/interfaces inherited from class org.hipparchus.random.AbstractWell
AbstractWell.IndexTable -
Field Summary
Fields inherited from class org.hipparchus.random.AbstractWell
index, v -
Constructor Summary
ConstructorsConstructorDescriptionCreates a new random number generator.Well44497b(int seed) Creates a new random number generator using a single int seed.Well44497b(int[] seed) Creates a new random number generator using an int array seed.Well44497b(long seed) Creates a new random number generator using a single long seed. -
Method Summary
Modifier and TypeMethodDescriptionprotected voidClears the cache used by the default implementation ofRandomGenerator.nextGaussian().booleanReturns the next pseudorandom, uniformly distributedbooleanvalue from this random number generator's sequence.voidnextBytes(byte[] bytes) Generates random bytes and places them into a user-supplied byte array.voidnextBytes(byte[] bytes, int start, int len) Generates random bytes and places them into a user-supplied byte array.doubleReturns the next pseudorandom, uniformly distributeddoublevalue between0.0and1.0from this random number generator's sequence.floatReturns the next pseudorandom, uniformly distributedfloatvalue between0.0and1.0from this random number generator's sequence.doubleReturns the next pseudorandom, Gaussian ("normally") distributeddoublevalue with mean0.0and standard deviation1.0from this random number generator's sequence.intnextInt()Returns the next pseudorandom, uniformly distributedintvalue from this random number generator's sequence.intnextInt(int n) Returns a pseudorandom, uniformly distributedintvalue between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.longnextLong()Returns the next pseudorandom, uniformly distributedlongvalue from this random number generator's sequence.longnextLong(long n) Returns a pseudorandom, uniformly distributedintvalue between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.voidsetSeed(int seed) Sets the seed of the underlying random number generator using anintseed.voidsetSeed(long seed) Sets the seed of the underlying random number generator using alongseed.toString()Methods inherited from class org.hipparchus.random.AbstractWell
setSeed
-
Constructor Details
-
Well44497b
public Well44497b()Creates a new random number generator.The instance is initialized using the current time as the seed.
-
Well44497b
public Well44497b(int seed) Creates a new random number generator using a single int seed.- Parameters:
seed- the initial seed (32 bits integer)
-
Well44497b
public Well44497b(int[] seed) Creates a new random number generator using an int array seed.- Parameters:
seed- the initial seed (32 bits integers array), if null the seed of the generator will be related to the current time
-
Well44497b
public Well44497b(long seed) Creates a new random number generator using a single long seed.- Parameters:
seed- the initial seed (64 bits integer)
-
-
Method Details
-
nextInt
public int nextInt()Returns the next pseudorandom, uniformly distributedintvalue from this random number generator's sequence.All 232 possible
intvalues should be produced with (approximately) equal probability.- Specified by:
nextIntin interfaceRandomGenerator- Returns:
- the next pseudorandom, uniformly distributed
intvalue from this random number generator's sequence
-
nextBoolean
public boolean nextBoolean()Returns the next pseudorandom, uniformly distributedbooleanvalue from this random number generator's sequence.- Returns:
- the next pseudorandom, uniformly distributed
booleanvalue from this random number generator's sequence
-
nextDouble
public double nextDouble()Returns the next pseudorandom, uniformly distributeddoublevalue between0.0and1.0from this random number generator's sequence.- Returns:
- the next pseudorandom, uniformly distributed
doublevalue between0.0and1.0from this random number generator's sequence
-
nextFloat
public float nextFloat()Returns the next pseudorandom, uniformly distributedfloatvalue between0.0and1.0from this random number generator's sequence.- Returns:
- the next pseudorandom, uniformly distributed
floatvalue between0.0and1.0from this random number generator's sequence
-
nextLong
public long nextLong()Returns the next pseudorandom, uniformly distributedlongvalue from this random number generator's sequence. All 264 possiblelongvalues should be produced with (approximately) equal probability.- Returns:
- the next pseudorandom, uniformly distributed
longvalue from this random number generator's sequence
-
nextBytes
public void nextBytes(byte[] bytes) Generates random bytes and places them into a user-supplied byte array. The number of random bytes produced is equal to the length of the byte array.- Parameters:
bytes- the non-null byte array in which to put the random bytes
-
nextBytes
public void nextBytes(byte[] bytes, int start, int len) Generates random bytes and places them into a user-supplied byte array.- Parameters:
bytes- the non-null byte array in which to put the random bytesstart- the starting index for inserting the generated bytes into the arraylen- the number of bytes to generate
-
setSeed
public void setSeed(int seed) Sets the seed of the underlying random number generator using anintseed.Sequences of values generated starting with the same seeds should be identical.
- Specified by:
setSeedin interfaceRandomGenerator- Parameters:
seed- the seed value
-
setSeed
public void setSeed(long seed) Sets the seed of the underlying random number generator using alongseed.Sequences of values generated starting with the same seeds should be identical.
- Specified by:
setSeedin interfaceRandomGenerator- Parameters:
seed- the seed value
-
nextInt
Returns a pseudorandom, uniformly distributedintvalue between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.- Specified by:
nextIntin interfaceRandomGenerator- Parameters:
n- the bound on the random number to be returned. Must be positive.- Returns:
- a pseudorandom, uniformly distributed
intvalue between 0 (inclusive) and n (exclusive). - Throws:
IllegalArgumentException- if n is not positive.
-
nextLong
public long nextLong(long n) Returns a pseudorandom, uniformly distributedintvalue between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.- Specified by:
nextLongin interfaceRandomGenerator- Parameters:
n- the bound on the random number to be returned. Must be positive.- Returns:
- a pseudorandom, uniformly distributed
intvalue between 0 (inclusive) and n (exclusive).
-
nextGaussian
public double nextGaussian()Returns the next pseudorandom, Gaussian ("normally") distributeddoublevalue with mean0.0and standard deviation1.0from this random number generator's sequence.- Specified by:
nextGaussianin interfaceRandomGenerator- Returns:
- the next pseudorandom, Gaussian ("normally") distributed
doublevalue with mean0.0and standard deviation1.0from this random number generator's sequence
-
clearCache
protected void clearCache()Clears the cache used by the default implementation ofRandomGenerator.nextGaussian(). -
toString
-