org.apache.hadoop.hbase.io.hfile

Class RandomDistribution.Binomial

java.lang.Object

org.apache.hadoop.hbase.io.hfile.RandomDistribution.Binomial

All Implemented Interfaces:

RandomDistribution.DiscreteRNG

Enclosing class:

RandomDistribution

public static final class RandomDistribution.Binomial
extends Object
implements RandomDistribution.DiscreteRNG

Binomial distribution. P(k)=select(n, k)*p^k*(1-p)^(n-k) (k = 0, 1, ..., n) P(k)=select(max-min-1, k-min)*p^(k-min)*(1-p)^(k-min)*(1-p)^(max-k-1)

Field Summary

Fields

Modifier and Type	Field and Description
private int	min
private int	n
private Random	random
private double[]	v

Constructor Summary

Constructors

Constructor and Description
Binomial(Random random, int min, int max, double p) Generate random integers from min (inclusive) to max (exclusive) following Binomial distribution.

Method Summary

Modifier and Type	Method and Description
int	nextInt() Get the next random number
private static double	power(double p, int k)
private static double	select(int n, int k)

Methods inherited from class java.lang.Object

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

Field Detail

random

private final Random random

min

private final int min

n

private final int n

v

private final double[] v

Constructor Detail

Binomial

public Binomial(Random random,
                int min,
                int max,
                double p)

Generate random integers from min (inclusive) to max (exclusive) following Binomial distribution.

Parameters:

random - The basic random number generator.

min - Minimum integer

max - maximum integer (exclusive).

p - parameter.

Method Detail

select

private static double select(int n,
                             int k)

power

private static double power(double p,
                            int k)

nextInt

public int nextInt()

Description copied from interface: RandomDistribution.DiscreteRNG

Get the next random number

Specified by:

nextInt in interface RandomDistribution.DiscreteRNG

Returns:

the next random number.

See Also:

RandomDistribution.DiscreteRNG.nextInt()