org.apache.hadoop.hbase.io.hfile

Class RandomDistribution.Zipf

java.lang.Object

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

All Implemented Interfaces:

RandomDistribution.DiscreteRNG

Enclosing class:

RandomDistribution

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

Zipf distribution. The ratio of the probabilities of integer i and j is defined as follows: P(i)/P(j)=((j-min+1)/(i-min+1))^sigma.

Field Summary

Fields

Modifier and Type	Field and Description
private static double	DEFAULT_EPSILON
private ArrayList<Integer>	k
private Random	random
private ArrayList<Double>	v

Constructor Summary

Constructors

Constructor and Description
Zipf(Random r, int min, int max, double sigma) Constructor
Zipf(Random r, int min, int max, double sigma, double epsilon) Constructor.

Method Summary

Modifier and Type	Method and Description
int	nextInt() Get the next random number

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_EPSILON

private static final double DEFAULT_EPSILON

See Also:

Constant Field Values

random

private final Random random

k

private final ArrayList<Integer> k

v

private final ArrayList<Double> v

Constructor Detail

Zipf

public Zipf(Random r,
            int min,
            int max,
            double sigma)

Constructor

Parameters:

r - The random number generator.

min - minimum integer (inclusvie)

max - maximum integer (exclusive)

sigma - parameter sigma. (sigma > 1.0)

Zipf

public Zipf(Random r,
            int min,
            int max,
            double sigma,
            double epsilon)

Constructor.

Parameters:

r - The random number generator.

min - minimum integer (inclusvie)

max - maximum integer (exclusive)

sigma - parameter sigma. (sigma > 1.0)

epsilon - Allowable error percentage (0 < epsilon < 1.0).

Method Detail

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()