Class BitsStreamGenerator

java.lang.Object
org.apache.commons.math.random.BitsStreamGenerator
All Implemented Interfaces:
RandomGenerator
Direct Known Subclasses:
AbstractWell, MersenneTwister

public abstract class BitsStreamGenerator extends Object implements RandomGenerator
Base class for random number generators that generates bits streams.
Since:
2.0
Version:
$Revision: 990655 $ $Date: 2010-08-29 23:49:40 +0200 (dim. 29 août 2010) $
  • Constructor Summary

    Constructors
    Constructor
    Description
    Creates a new random number generator.
  • Method Summary

    Modifier and Type
    Method
    Description
    protected abstract int
    next(int bits)
    Generate next pseudorandom number.
    boolean
    Returns the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence.
    void
    nextBytes(byte[] bytes)
    Generates random bytes and places them into a user-supplied byte array.
    double
    Returns the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence.
    float
    Returns the next pseudorandom, uniformly distributed float value between 0.0 and 1.0 from this random number generator's sequence.
    double
    Returns the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence.
    int
    Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence.
    int
    nextInt(int n)
    Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
    long
    Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence.
    abstract void
    setSeed(int seed)
    Sets the seed of the underlying random number generator using an int seed.
    abstract void
    setSeed(int[] seed)
    Sets the seed of the underlying random number generator using an int array seed.
    abstract void
    setSeed(long seed)
    Sets the seed of the underlying random number generator using a long seed.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • BitsStreamGenerator

      public BitsStreamGenerator()
      Creates a new random number generator.
  • Method Details

    • setSeed

      public abstract void setSeed(int seed)
      Sets the seed of the underlying random number generator using an int seed.

      Sequences of values generated starting with the same seeds should be identical.

      Specified by:
      setSeed in interface RandomGenerator
      Parameters:
      seed - the seed value
    • setSeed

      public abstract void setSeed(int[] seed)
      Sets the seed of the underlying random number generator using an int array seed.

      Sequences of values generated starting with the same seeds should be identical.

      Specified by:
      setSeed in interface RandomGenerator
      Parameters:
      seed - the seed value
    • setSeed

      public abstract void setSeed(long seed)
      Sets the seed of the underlying random number generator using a long seed.

      Sequences of values generated starting with the same seeds should be identical.

      Specified by:
      setSeed in interface RandomGenerator
      Parameters:
      seed - the seed value
    • next

      protected abstract int next(int bits)
      Generate next pseudorandom number.

      This method is the core generation algorithm. It is used by all the public generation methods for the various primitive types nextBoolean(), nextBytes(byte[]), nextDouble(), nextFloat(), nextGaussian(), nextInt(), next(int) and nextLong().

      Parameters:
      bits - number of random bits to produce
      Returns:
      random bits generated
    • nextBoolean

      public boolean nextBoolean()
      Returns the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence.
      Specified by:
      nextBoolean in interface RandomGenerator
      Returns:
      the next pseudorandom, uniformly distributed boolean value 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.
      Specified by:
      nextBytes in interface RandomGenerator
      Parameters:
      bytes - the non-null byte array in which to put the random bytes
    • nextDouble

      public double nextDouble()
      Returns the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence.
      Specified by:
      nextDouble in interface RandomGenerator
      Returns:
      the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence
    • nextFloat

      public float nextFloat()
      Returns the next pseudorandom, uniformly distributed float value between 0.0 and 1.0 from this random number generator's sequence.
      Specified by:
      nextFloat in interface RandomGenerator
      Returns:
      the next pseudorandom, uniformly distributed float value between 0.0 and 1.0 from this random number generator's sequence
    • nextGaussian

      public double nextGaussian()
      Returns the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence.
      Specified by:
      nextGaussian in interface RandomGenerator
      Returns:
      the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence
    • nextInt

      public int nextInt()
      Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence. All 232 possible int values should be produced with (approximately) equal probability.
      Specified by:
      nextInt in interface RandomGenerator
      Returns:
      the next pseudorandom, uniformly distributed int value from this random number generator's sequence
    • nextInt

      public int nextInt(int n) throws IllegalArgumentException
      Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
      Specified by:
      nextInt in interface RandomGenerator
      Parameters:
      n - the bound on the random number to be returned. Must be positive.
      Returns:
      a pseudorandom, uniformly distributed int value between 0 (inclusive) and n (exclusive).
      Throws:
      IllegalArgumentException - if n is not positive.
    • nextLong

      public long nextLong()
      Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence. All 264 possible long values should be produced with (approximately) equal probability.
      Specified by:
      nextLong in interface RandomGenerator
      Returns:
      the next pseudorandom, uniformly distributed long value from this random number generator's sequence