Iota.html

Iota.java

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package blog.distrib;

import java.util.*;
import blog.*;
import common.Util;

CPD that takes a set of size one as an argument, and defines a probability distribution concentrated on the single element of that set. If the argument set is empty, the distribution is concentrated on Model.NULL. If the set has size greater than one, the getProb and sampleVal methods throw IllegalArgumentExceptions.

The name comes from the iota operator in logic.


public class Iota extends DetCondProbDistrib {

Creates an Iota CPD.


    public Iota() {
    }

Creates an Iota CPD. The CPD takes no parameters.

Throws: IllegalArgumentException if params is non-empty


    public Iota(List params) {
	if (!params.isEmpty()) {
	    throw new IllegalArgumentException
		("Iota CPD does not take any parameters.");
	}
    }

Takes a single argument, namely a set S. If S is empty, returns Model.NULL. If S has a single element, returns that element. If S has more than one element, throws an IllegalArgumentException. other than a single argument of class Set.

Throws: IllegalArgumentException if args contains anything


    public Object getChildValue(List args) {
	Set s = processArgs(args); // throws exception if size > 1
	if (s.isEmpty()) {
	    return Model.NULL;
	}
	return s.iterator().next();
    }

    private Set processArgs(List args) {
	if (args.size() != 1) {
	    throw new IllegalArgumentException
		("Iota CPD takes exactly one argument.");
	}
	if (!(args.get(0) instanceof Set)) {
	    throw new IllegalArgumentException
		("Iota CPD takes an argument of class Set, not one of " 
		 + args.get(0).getClass() + ".");
	}

	Set s = (Set) args.get(0);
	if (s.size() > 1) {
	    throw new IllegalArgumentException
		("Set passed to Iota CPD has more than one element: " + s);
	}

	return s;
    }
}

This file was generated on Tue Jun 08 17:53:47 PDT 2010 from file Iota.java
by the ilog.language.tools.Hilite Java tool written by Hassan Aït-Kaci