Package jline.lang.processes

Class Zipf

java.lang.Object

jline.lang.processes.Distribution

jline.lang.processes.DiscreteDistribution

jline.lang.processes.Zipf

All Implemented Interfaces:

Serializable

public class Zipf
extends DiscreteDistribution

A Zipf-like probability distribution

See Also:

• Serialized Form

Field Summary

Fields inherited from class jline.lang.processes.Distribution

immediate, mean, name, numParam, params, support

Constructor Summary

Constructors

Constructor	Description
Zipf(double s, int n)	Construct a Zipf-like distribution

Method Summary

Modifier and Type	Method	Description
double	evalCDF(double t)	Evaluates the cumulative distribution function at t
Matrix	evalPMF()
Matrix	evalPMF(List<Double> t)	Evaluates the probability mass function at t
static double	genHarmonic(double s, int n)	Generate harmonic numbers to normalize a Zipf-like distribution on n items with shape s
double	getMean()	Computes the distribution mean
double	getSCV()	Computes the squared coefficient of variation == variance/mean^2
double	getSkewness()
static void	main(String[] args)
double[]	sample(int n)	Gets n samples from the distribution
double[]	sample(int n, Random random)

Methods inherited from class jline.lang.processes.DiscreteDistribution

evalPMF, evalPMF

Methods inherited from class jline.lang.processes.Distribution

evalProbInterval, getName, getNumParams, getParam, getRate, getSupport, getVar, isContinuous, isDisabled, isDiscrete, isImmediate, setNumParams, setParam

Methods inherited from class java.lang.Object

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

Constructor Details

Zipf

public Zipf(double s,
 int n)

Construct a Zipf-like distribution

Parameters:

s - - the shape

n - - number of items

Method Details

genHarmonic

public static double genHarmonic(double s,
 int n)

Generate harmonic numbers to normalize a Zipf-like distribution on n items with shape s

main

public static void main(String[] args)

getMean

public double getMean()

Computes the distribution mean

Specified by:

getMean in class Distribution

Returns:

- the mean of the distribution

getSCV

public double getSCV()

Computes the squared coefficient of variation == variance/mean^2

Specified by:

getSCV in class Distribution

Returns:

- the squared coefficient of variation

getSkewness

public double getSkewness()

Specified by:

getSkewness in class Distribution

sample

public double[] sample(int n)

Gets n samples from the distribution

Overrides:

sample in class Distribution

Parameters:

n - - the number of samples

Returns:

- n samples from the distribution

sample

public double[] sample(int n,
 Random random)

Specified by:

sample in class Distribution

evalCDF

public double evalCDF(double t)

Evaluates the cumulative distribution function at t

Specified by:

evalCDF in class Distribution

Parameters:

t - - the point where the cdf will be evaluated

Returns:

- the cdf evaluated at t

evalPMF

public Matrix evalPMF()

evalPMF

public Matrix evalPMF(List<Double> t)

Evaluates the probability mass function at t

Overrides:

evalPMF in class DiscreteDistribution

Parameters:

t - - the point where the pmf will be evaluated

Returns:

- the pfm evaluated at t