javanpst.distributions.common.discrete

Class PoissonDistribution

java.lang.Object

javanpst.distributions.common.discrete.PoissonDistribution

All Implemented Interfaces:

Distribution

public final class PoissonDistribution
extends java.lang.Object
implements Distribution

A poisson distribution, with a specified mean

Constructor Summary

Constructors

Constructor and Description
PoissonDistribution() Default builder.
PoissonDistribution(double mean) Builder.
PoissonDistribution(PoissonDistribution old) Copy constructor Creates a copy of a given Poisson distribution

Method Summary

Modifier and Type	Method and Description
double	computeCumulativeProbability(double value) Computes cumulative probability at a given point of the Poisson distribution.
double	computeProbability(double value) Computes mass probability at a given point of the Poisson distribution.
double	getMean() Gets the mean of the distribution
void	setMean(double value) Sets the mean of the distribution.
java.lang.String	toString() To String method.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

PoissonDistribution

public PoissonDistribution()

Default builder. Creates a Poisson distribution with mean = 1.0

PoissonDistribution

public PoissonDistribution(double mean)

Builder. Creates a Poisson distribution with a given mean

Parameters:

mean - Mean for the distribution

PoissonDistribution

public PoissonDistribution(PoissonDistribution old)

Copy constructor Creates a copy of a given Poisson distribution

Parameters:

old - Poisson distribution to copy

Method Detail

setMean

public void setMean(double value)

Sets the mean of the distribution. Mean must be positive

Parameters:

value - Mean value

getMean

public double getMean()

Gets the mean of the distribution

Returns:

Mean value

computeProbability

public double computeProbability(double value)

Computes mass probability at a given point of the Poisson distribution. Value given is converted to integer before computing probability.

Specified by:

computeProbability in interface Distribution

Parameters:

value - point selected

Returns:

mass probability at 'value'

computeCumulativeProbability

public double computeCumulativeProbability(double value)

Computes cumulative probability at a given point of the Poisson distribution. Value given is converted to integer before computing probability.

Specified by:

computeCumulativeProbability in interface Distribution

Parameters:

value - point selected

Returns:

cumulative probability at 'value'

toString

public java.lang.String toString()

To String method.

Overrides:

toString in class java.lang.Object

Returns:

string representation of the distribution