squidpony.squidmath

Class ExponentialDistribution

java.lang.Object

squidpony.squidmath.ExponentialDistribution

All Implemented Interfaces:

IDistribution

public class ExponentialDistribution
extends java.lang.Object
implements IDistribution

An IDistribution that implements the Exponential distribution. Takes lambda as a parameter during construction (default 1), and lambda also has getters/setters.
Created by Tommy Ettinger on 11/23/2019.

Nested Class Summary

Nested classes/interfaces inherited from interface squidpony.squidmath.IDistribution

IDistribution.SimpleDistribution

Field Summary

Fields

Modifier and Type	Field and Description
static ExponentialDistribution	instance
static ExponentialDistribution	instance_0_5
static ExponentialDistribution	instance_1_5

Fields inherited from interface squidpony.squidmath.IDistribution

EXCLUSIVE_ONE, EXCLUSIVE_ZERO

Constructor Summary

Constructors

Constructor and Description
ExponentialDistribution()
ExponentialDistribution(double lambda)

Method Summary

Modifier and Type	Method and Description
double	getLambda()
double	getLowerBound() The lower inclusive bound is 0 while lambda is positive; it is negative infinity if lambda is negative.
double	getMean() Gets the mean value of this distribution (1.0 / lambda).
double	getUpperBound() The upper inclusive bound is infinity while lambda is positive; it is 0 if lambda is negative.
double	nextDouble(IRNG rng) Gets a double between IDistribution.getLowerBound() and IDistribution.getUpperBound() that obeys this distribution.
void	setLambda(double lambda)

Methods inherited from class java.lang.Object

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

Field Detail

instance

public static final ExponentialDistribution instance

instance_0_5

public static final ExponentialDistribution instance_0_5

instance_1_5

public static final ExponentialDistribution instance_1_5

Constructor Detail

ExponentialDistribution

public ExponentialDistribution()

ExponentialDistribution

public ExponentialDistribution(double lambda)

Method Detail

getLambda

public double getLambda()

setLambda

public void setLambda(double lambda)

nextDouble

public double nextDouble(IRNG rng)

Description copied from interface: IDistribution

Gets a double between IDistribution.getLowerBound() and IDistribution.getUpperBound() that obeys this distribution.

Specified by:

nextDouble in interface IDistribution

Parameters:

rng - an IRNG, such as RNG or GWTRNG, that this will get one or more random numbers from

Returns:

a double within the range of IDistribution.getLowerBound() and IDistribution.getUpperBound(), both inclusive

getLowerBound

public double getLowerBound()

The lower inclusive bound is 0 while lambda is positive; it is negative infinity if lambda is negative.

Specified by:

getLowerBound in interface IDistribution

Returns:

zero, or negative infinity if lambda is negative.

getUpperBound

public double getUpperBound()

The upper inclusive bound is infinity while lambda is positive; it is 0 if lambda is negative.

Specified by:

getUpperBound in interface IDistribution

Returns:

positive infinity, or zero if lambda is negative.

getMean

public double getMean()

Gets the mean value of this distribution (1.0 / lambda).

Specified by:

getMean in interface IDistribution

Returns:

the mean value of this distribution (1.0 / lambda)