opendial.bn.distribs

Class SingleValueDistribution

java.lang.Object

opendial.bn.distribs.SingleValueDistribution

All Implemented Interfaces:

IndependentDistribution, ProbDistribution

public class SingleValueDistribution
extends java.lang.Object
implements IndependentDistribution

Representation of a distribution with a single value associated with a probability of 1.0. Although this can also be represented in a categorical table, this representation is much faster than operating on a full table.

Field Summary

Fields inherited from interface opendial.bn.distribs.IndependentDistribution

log

Constructor Summary

Constructors

Constructor and Description
SingleValueDistribution(java.lang.String variable, java.lang.String value) Creates a new single-value distribution
SingleValueDistribution(java.lang.String variable, Value value) Creates a new single-value distribution

Method Summary

Modifier and Type	Method and Description
IndependentDistribution	copy() Copies the distribution
boolean	equals(java.lang.Object o) Returns true if the assignment is identical to the one in this distribution, otherwise false
org.w3c.dom.Node	generateXML(org.w3c.dom.Document document) Returns the XML representation (as a categorical table)
Value	getBest() Returns the value
double	getProb(Value value) Returns 1.0 if the value is equal to the one in the distribution, and 0.0 otherwise.
java.util.Set<Value>	getValues() Returns a singleton set with the value.
java.lang.String	getVariable() Returns the variable label
int	hashCode() Returns the distribution's hashcode
void	modifyVariableId(java.lang.String oldId, java.lang.String newId) Modifies the variable label
boolean	pruneValues(double threshold) Does nothing
Value	sample() Returns the value.
ContinuousDistribution	toContinuous() Returns a continuous representation of the distribution (if possible)
CategoricalTable	toDiscrete() Returns the categorical table corresponding to the distribution.
java.lang.String	toString() Returns the string representation for this distribution

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface opendial.bn.distribs.IndependentDistribution

getInputVariables, getPosterior, getProb, getProb, getProb, getProb, getProb, getProbDistrib, sample

Constructor Detail

SingleValueDistribution

public SingleValueDistribution(java.lang.String variable,
                               Value value)

Creates a new single-value distribution

Parameters:

variable - the variable label

value - the value

SingleValueDistribution

public SingleValueDistribution(java.lang.String variable,
                               java.lang.String value)

Creates a new single-value distribution

Parameters:

variable - the variable label

value - the value (as a string)

Method Detail

getVariable

public java.lang.String getVariable()

Returns the variable label

Specified by:

getVariable in interface ProbDistribution

Returns:

the name of the random variable

pruneValues

public boolean pruneValues(double threshold)

Does nothing

Specified by:

pruneValues in interface ProbDistribution

Parameters:

threshold - the threshold to apply for the pruning

Returns:

true if at least one value has been removed, false otherwise

modifyVariableId

public void modifyVariableId(java.lang.String oldId,
                             java.lang.String newId)

Modifies the variable label

Specified by:

modifyVariableId in interface ProbDistribution

Parameters:

oldId - the old identifier to replace

newId - the new identifier

getProb

public double getProb(Value value)

Returns 1.0 if the value is equal to the one in the distribution, and 0.0 otherwise.

Specified by:

getProb in interface IndependentDistribution

Parameters:

value - the value for the random variable

Returns:

the associated probability, if one exists.

sample

public Value sample()

Returns the value.

Specified by:

sample in interface IndependentDistribution

Returns:

the sampled value

getValues

public java.util.Set<Value> getValues()

Returns a singleton set with the value.

Specified by:

getValues in interface IndependentDistribution

Specified by:

getValues in interface ProbDistribution

Returns:

the possible values for the distribution

toContinuous

public ContinuousDistribution toContinuous()

Returns a continuous representation of the distribution (if possible)

Specified by:

toContinuous in interface IndependentDistribution

Returns:

the distribution in a continuous form be converted to a continuous form

toDiscrete

public CategoricalTable toDiscrete()

Returns the categorical table corresponding to the distribution.

Specified by:

toDiscrete in interface IndependentDistribution

Returns:

the distribution in a discrete form.

getBest

public Value getBest()

Returns the value

Specified by:

getBest in interface IndependentDistribution

Returns:

the maximum-probability value (discrete) or the mean value (continuous)

generateXML

public org.w3c.dom.Node generateXML(org.w3c.dom.Document document)

Returns the XML representation (as a categorical table)

Specified by:

generateXML in interface IndependentDistribution

Parameters:

document - the XML node to which the node will be attached

Returns:

the corresponding XML node

copy

public IndependentDistribution copy()

Copies the distribution

Specified by:

copy in interface IndependentDistribution

Specified by:

copy in interface ProbDistribution

Returns:

the copied distribution

hashCode

public int hashCode()

Returns the distribution's hashcode

Overrides:

hashCode in class java.lang.Object

Returns:

the hashcode

toString

public java.lang.String toString()

Returns the string representation for this distribution

Overrides:

toString in class java.lang.Object

Returns:

the string

equals

public boolean equals(java.lang.Object o)

Returns true if the assignment is identical to the one in this distribution, otherwise false

Overrides:

equals in class java.lang.Object

Parameters:

o - the object to compare

Returns:

true if equals, false otherwise