blog.distrib
Class UniformChoice

java.lang.Object
  blog.AbstractCondProbDistrib
      blog.distrib.UniformChoice

All Implemented Interfaces:

CondProbDistrib

public class UniformChoice
extends AbstractCondProbDistrib

CPD that takes a set of objects (an instance of the ObjectSet interface) as an argument, and defines a uniform distribution over this set.

Constructor Summary

UniformChoice()
Creates a UniformChoice CPD.

UniformChoice(java.util.List params)
Creates a UniformChoice CPD.

Method Summary

double	getProb(java.util.List args, java.lang.Object value) Takes a single argument, namely a set S.
java.lang.Object	sampleVal(java.util.List args, Type childType) Takes a single argument, namely a finite set S.

Methods inherited from class blog.AbstractCondProbDistrib

getLogProb, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

UniformChoice

public UniformChoice()

Creates a UniformChoice CPD. This constructor is not used by the parser, which looks for a constructor taking a List as an argument. Instead, it's used when we create a UniformChoice CPD in the program.

UniformChoice

public UniformChoice(java.util.List params)

Creates a UniformChoice CPD. The CPD takes no parameters.

Throws:

java.lang.IllegalArgumentException - if params is non-empty

Method Detail

getProb

public double getProb(java.util.List args,
                      java.lang.Object value)

Takes a single argument, namely a set S. If S is non-empty, returns 1 / |S| if value is in S, and otherwise 0. If S is empty, returns 1 if the value is Model.NULL, and 0 otherwise.

Throws:

java.lang.IllegalArgumentException - if args contains anything other than a single argument of class ObjectSet.

sampleVal

public java.lang.Object sampleVal(java.util.List args,
                                  Type childType)

Takes a single argument, namely a finite set S. Returns an element of S selected uniformly at random. If S is empty, returns Model.NULL.

Throws:

java.lang.IllegalArgumentException - if args contains anything other than a single argument of class ObjectSet.