ValueSorter.java

package edu.nd.nina.util;

/* Copyright (C) 2002 Univ. of Massachusetts Amherst, Computer Science Dept.
 This file is part of "MALLET" (MAchine Learning for LanguagE Toolkit).
 http://www.cs.umass.edu/~mccallum/mallet
 This software is provided under the terms of the Common Public License,
 version 1.0, as published by http://www.opensource.org.  For further
 information, see the file `LICENSE' included with this distribution. */

/**
 * This class is contains a comparator for use in sorting integers that have
 * associated floating point values. One example would be sorting words by
 * probability in a Naive Bayes model. Ties are broken by the ID. <code><pre>
 *     IDSorter[] sortedIDs = new IDSorter[n];
 *     for (int i=0; i<n; i++) {
 *       sortedIDs[i] = new IDSorter(i, weights[i]);
 *     }
 *     Arrays.sort(sortedIDs);
 *     
 *     for (int i=0; i<10; i++) {
 *   </pre></code>
 * 
 * @author David Mimno
 */

public class ValueSorter implements Comparable<ValueSorter> {
	int id;
	double p;

	public ValueSorter(int id, double p) {
		this.id = id;
		this.p = p;
	}

	public ValueSorter(int id, int p) {
		this.id = id;
		this.p = p;
	}

	public final int compareTo(ValueSorter o2) {

		if (p > o2.p) {
			return -1;
		} else if (p < o2.p) {
			return 1;
		}

		// p == otherP, sort by ID

		int otherID = o2.id;

		if (id > otherID) {
			return -1;
		} else if (id < otherID) {
			return 1;
		}

		return 0;
	}

	public int getID() {
		return id;
	}

	public double getWeight() {
		return p;
	}

	/** Reinitialize an IDSorter */
	public void set(int id, double p) {
		this.id = id;
		this.p = p;
	}
}