Package smile.math.random

Class UniversalGenerator

java.lang.Object
smile.math.random.UniversalGenerator
All Implemented Interfaces:
RandomNumberGenerator
public class UniversalGenerator extends Object implements RandomNumberGenerator
The so-called "Universal Generator" based on multiplicative congruential method, which originally appeared in "Toward a Universal Random Number Generator" by Marsaglia, Zaman and Tsang. It was later modified by F. James in "A Review of Pseudo-random Number Generators". It passes ALL the tests for random number generators and has a period of 2144. It is completely portable (gives bit-identical results on all machines with at least 24-bit mantissas in the floating point representation).

  • Constructor Summary

    Constructors
    Constructor
    Description
    UniversalGenerator()
    Initialize Random with default seed.
    UniversalGenerator(int seed)
    Initialize Random with a specified integer seed
    UniversalGenerator(long seed)
    Initialize Random with a specified long seed

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    next(int numbits)
    Returns up to 32 random bits.
    double
    nextDouble()
    Returns the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence.
    void
    nextDoubles(double[] d)
    Returns a vector of pseudorandom, uniformly distributed double values between 0.0 and 1.0 from this random number generator's sequence.
    int
    nextInt()
    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
    nextLong()
    Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence.
    void
    setSeed(long seed)
    Initialize the random generator with a seed.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • UniversalGenerator

      public UniversalGenerator()
      Initialize Random with default seed.

    • UniversalGenerator

      public UniversalGenerator(int seed)
      Initialize Random with a specified integer seed
      Parameters:
      seed - the seed of random numbers.

    • UniversalGenerator

      public UniversalGenerator(long seed)
      Initialize Random with a specified long seed
      Parameters:
      seed - the seed of random numbers.

  • Method Details

    • setSeed

      public void setSeed(long seed)
      Description copied from interface: RandomNumberGenerator
      Initialize the random generator with a seed.
      Specified by:
      setSeed in interface RandomNumberGenerator
      Parameters:
      seed - the seed of random numbers.

    • nextDouble

      public double nextDouble()
      Description copied from interface: RandomNumberGenerator
      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 RandomNumberGenerator
      Returns:
      random number.

    • nextDoubles

      public void nextDoubles(double[] d)
      Description copied from interface: RandomNumberGenerator
      Returns a vector of pseudorandom, uniformly distributed double values between 0.0 and 1.0 from this random number generator's sequence.
      Specified by:
      nextDoubles in interface RandomNumberGenerator
      Parameters:
      d - the output random numbers.

    • next

      public int next(int numbits)
      Description copied from interface: RandomNumberGenerator
      Returns up to 32 random bits.
      Specified by:
      next in interface RandomNumberGenerator
      Parameters:
      numbits - the number of random bits to generate.
      Returns:
      random bits.

    • nextInt

      public int nextInt()
      Description copied from interface: RandomNumberGenerator
      Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence.
      Specified by:
      nextInt in interface RandomNumberGenerator
      Returns:
      random number.

    • nextInt

      public int nextInt(int n)
      Description copied from interface: RandomNumberGenerator
      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 RandomNumberGenerator
      Parameters:
      n - the upper bound of random number (exclusive).
      Returns:
      random number.

    • nextLong

      public long nextLong()
      Description copied from interface: RandomNumberGenerator
      Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence.
      Specified by:
      nextLong in interface RandomNumberGenerator
      Returns:
      random number.