smile.math

Class Random

java.lang.Object

smile.math.Random

public class Random
extends Object

This is a high quality random number generator as a replacement of the standard Random class of Java system.

Author:

Haifeng Li

Constructor Summary

Constructors

Constructor and Description
Random() Initialize with default random number generator engine.
Random(long seed) Initialize with given seed for default random number generator engine.
Random(RandomNumberGenerator rng) Initialize with given random number generator engine.

Method Summary

Methods

Modifier and Type	Method and Description
double	nextDouble() Generator a random number uniformly distributed in [0, 1).
double	nextDouble(double lo, double hi) Generate a uniform random number in the range [lo, hi)
void	nextDoubles(double[] d) Generate n uniform random numbers in the range [0, 1)
void	nextDoubles(double[] d, double lo, double hi) Generate n uniform random numbers in the range [lo, hi)
int	nextInt() Returns a random integer.
int	nextInt(int n) Returns a random integer in [0, n).
long	nextLong()
void	permutate(double[] x) Generates a permutation of given array.
void	permutate(float[] x) Generates a permutation of given array.
int[]	permutate(int n) Generates a permutation of 0, 1, 2, ..., n-1, which is useful for sampling without replacement.
void	permutate(int[] x) Generates a permutation of given array.
void	permutate(Object[] x) Generates a permutation of given array.

Methods inherited from class java.lang.Object

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

Constructor Detail

Random

public Random()

Initialize with default random number generator engine.

Random

public Random(long seed)

Initialize with given seed for default random number generator engine.

Random

public Random(RandomNumberGenerator rng)

Initialize with given random number generator engine.

Method Detail

nextDouble

public double nextDouble()

Generator a random number uniformly distributed in [0, 1).

Returns:

a pseudo random number

nextDoubles

public void nextDoubles(double[] d)

Generate n uniform random numbers in the range [0, 1)

Parameters:

d - array of random numbers to be generated

nextDouble

public double nextDouble(double lo,
                double hi)

Generate a uniform random number in the range [lo, hi)

Parameters:

lo - lower limit of range

hi - upper limit of range

Returns:

a uniform random real in the range [lo, hi)

nextDoubles

public void nextDoubles(double[] d,
               double lo,
               double hi)

Generate n uniform random numbers in the range [lo, hi)

Parameters:

lo - lower limit of range

hi - upper limit of range

d - array of random numbers to be generated

nextInt

public int nextInt()

Returns a random integer.

nextInt

public int nextInt(int n)

Returns a random integer in [0, n).

nextLong

public long nextLong()

permutate

public int[] permutate(int n)

Generates a permutation of 0, 1, 2, ..., n-1, which is useful for sampling without replacement.

permutate

public void permutate(int[] x)

Generates a permutation of given array.

permutate

public void permutate(float[] x)

Generates a permutation of given array.

permutate

public void permutate(double[] x)

Generates a permutation of given array.

permutate

public void permutate(Object[] x)

Generates a permutation of given array.