Package org.apache.commons.math4.legacy.distribution

Class EnumeratedIntegerDistribution

java.lang.Object

org.apache.commons.math4.legacy.distribution.AbstractIntegerDistribution

org.apache.commons.math4.legacy.distribution.EnumeratedIntegerDistribution

All Implemented Interfaces:

org.apache.commons.statistics.distribution.DiscreteDistribution

public class EnumeratedIntegerDistribution
extends AbstractIntegerDistribution

Implementation of an integer-valued EnumeratedDistribution.

Values with zero-probability are allowed but they do not extend the support.
Duplicate values are allowed. Probabilities of duplicate values are combined when computing cumulative probabilities and statistics.

Since:

3.2

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.commons.statistics.distribution.DiscreteDistribution

org.apache.commons.statistics.distribution.DiscreteDistribution.Sampler

Field Summary

Fields

Modifier and Type	Field	Description
protected EnumeratedDistribution<Integer>	innerDistribution	EnumeratedDistribution instance (using the Integer wrapper) used to generate the pmf.

Constructor Summary

Constructors

Constructor	Description
EnumeratedIntegerDistribution(int[] data)	Create a discrete integer-valued distribution from the input data.
EnumeratedIntegerDistribution(int[] singletons, double[] probabilities)	Create a discrete distribution.

Method Summary

Modifier and Type	Method	Description
org.apache.commons.statistics.distribution.DiscreteDistribution.Sampler	createSampler(org.apache.commons.rng.UniformRandomProvider rng)	Refer to EnumeratedDistribution.Sampler for implementation details.
double	cumulativeProbability(int x)
double	getMean()
int	getSupportLowerBound()	Returns the lowest value with non-zero probability.
int	getSupportUpperBound()	Returns the highest value with non-zero probability.
double	getVariance()
double	probability(int x)

Methods inherited from class org.apache.commons.math4.legacy.distribution.AbstractIntegerDistribution

inverseCumulativeProbability, logProbability, probability, sample, solveInverseCumulativeProbability

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.statistics.distribution.DiscreteDistribution

inverseSurvivalProbability, survivalProbability

Field Detail

innerDistribution

protected final EnumeratedDistribution<Integer> innerDistribution

EnumeratedDistribution instance (using the Integer wrapper) used to generate the pmf.

Constructor Detail

EnumeratedIntegerDistribution

public EnumeratedIntegerDistribution(int[] singletons,
                                     double[] probabilities)
                              throws DimensionMismatchException,
                                     NotPositiveException,
                                     MathArithmeticException,
                                     NotFiniteNumberException,
                                     NotANumberException

Create a discrete distribution.

Parameters:

singletons - array of random variable values.

probabilities - array of probabilities.

Throws:

DimensionMismatchException - if singletons.length != probabilities.length

NotPositiveException - if any of the probabilities are negative.

NotFiniteNumberException - if any of the probabilities are infinite.

NotANumberException - if any of the probabilities are NaN.

MathArithmeticException - all of the probabilities are 0.

EnumeratedIntegerDistribution

public EnumeratedIntegerDistribution(int[] data)

Create a discrete integer-valued distribution from the input data. Values are assigned mass based on their frequency.

Parameters:

data - input dataset

Method Detail

probability

public double probability(int x)

cumulativeProbability

public double cumulativeProbability(int x)

getMean

public double getMean()

Returns:

sum(singletons[i] * probabilities[i])

getVariance

public double getVariance()

Returns:

sum((singletons[i] - mean) ^ 2 * probabilities[i])

getSupportLowerBound

public int getSupportLowerBound()

Returns the lowest value with non-zero probability.

Returns:

the lowest value with non-zero probability.

getSupportUpperBound

public int getSupportUpperBound()

Returns the highest value with non-zero probability.

Returns:

the highest value with non-zero probability.

createSampler

public org.apache.commons.statistics.distribution.DiscreteDistribution.Sampler createSampler(org.apache.commons.rng.UniformRandomProvider rng)

Refer to EnumeratedDistribution.Sampler for implementation details.

Specified by:

createSampler in interface org.apache.commons.statistics.distribution.DiscreteDistribution

Overrides:

createSampler in class AbstractIntegerDistribution