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MALLET is a Java-based package for statistical natural language processing, document classification, clustering, topic modeling, information extraction, and other machine learning applications to text.

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/* 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. */



/** 
   @author Aron Culotta [email protected]
 */

package cc.mallet.classify;

import cc.mallet.pipe.Pipe;
import cc.mallet.types.FeatureVector;
import cc.mallet.types.Instance;
import cc.mallet.types.LabelVector;

/** 
 * Classification methods of Winnow2 algorithm.
 * @see WinnowTrainer
 */
public class Winnow extends Classifier{
	/**
	 *array of weights, one for each feature, initialized to 1
	 */
	double [][] weights;
	/**
	 *threshold for sum of wi*xi in formulating guess 
	 */
	double theta;
	
	/**
	 * Passes along data pipe and weights from 
	 * {@link #WinnowTrainer WinnowTrainer}
	 * @param dataPipe needed for dictionary, labels, feature vectors, etc
	 * @param newWeights weights calculated during training phase
	 * @param theta value used for threshold
	 * @param idim i dimension of weights array
	 * @param jdim j dimension of weights array
	 */
	public Winnow (Pipe dataPipe,
								 double [][]newWeights, double theta, 
								 int idim, int jdim){
		super (dataPipe);
		this.theta = theta;
		this.weights = new double[idim][jdim];
		for(int i=0; i