Measure.java

/*
 * Ivory: A Hadoop toolkit for web-scale information retrieval
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License. You may
 * obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0 
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

package ivory.ltr;

import java.util.Comparator;

/**
 * @author Don Metzler
 *
 */
public abstract class Measure {

	public abstract double evaluate(ScoreTable table);

	public class ScoreGradePair {
		public float score;
		public float grade;

		public ScoreGradePair(float s, float g) {
			score = s;
			grade = g;
		}
	}
	
	public class ScoreComparator implements Comparator<ScoreGradePair> {

		public int compare(ScoreGradePair o1, ScoreGradePair o2) {
			if(o1.score > o2.score) {
				return -1;
			}
			else if(o1.score < o2.score) {
				return 1;
			}
			return 0;
		}		
	}

	public class GradeComparator implements Comparator<ScoreGradePair> {

		public int compare(ScoreGradePair o1, ScoreGradePair o2) {
			if(o1.grade > o2.grade) {
				return -1;
			}
			else if(o1.grade < o2.grade) {
				return 1;
			}
			return 0;
		}		
	}
}