WordClusterPaths.java

/*Copyright 2014, Language Technologies Institute, Carnegie Mellon
University

    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 cmu.arktweetnlp.impl.features;

import java.io.BufferedReader;
import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.regex.Pattern;

import cmu.arktweetnlp.Twokenize;
import cmu.arktweetnlp.impl.features.FeatureExtractor.FeatureExtractorInterface;
import cmu.arktweetnlp.impl.features.FeatureExtractor.PositionFeaturePairs;
import cmu.arktweetnlp.util.BasicFileIO;
import edu.stanford.nlp.util.StringUtils;

/**
 * Brown word clusters: features are path prefixes down the tree. 
 **/
public class WordClusterPaths implements FeatureExtractorInterface {
	
	/** TODO this should be moved into config somehow **/
	public static String clusterResourceName = "res/arktweetnlp/50mpaths2";
	
	public static HashMap<String,String> wordToPath;

	public WordClusterPaths() throws IOException {
//		log.info("Loading clusters");
		
		//read in paths file
		BufferedReader bReader = BasicFileIO.getResourceReader(clusterResourceName);
		String[] splitline = new String[3];
		String line=BasicFileIO.getLine(bReader);
		wordToPath = new HashMap<String,String>(); 
		while(line != null){
			splitline = line.split("\\t");
			wordToPath.put(splitline[1], splitline[0]);
			line = BasicFileIO.getLine(bReader);
		}			
//		log.info("Finished loading clusters");
	}
	
	public void addFeatures(List<String> tokens, PositionFeaturePairs pairs) {
		String bitstring = null;
		for (int t=0; t < tokens.size(); t++) {
			String tok = tokens.get(t);
		    String normaltok = FeatureUtil.normalize(tok);
		    bitstring = wordToPath.get(normaltok);
		    if (bitstring == null){
		    	for (String fuzz : FeatureUtil.fuzztoken(normaltok, true)){
		    		bitstring = wordToPath.get(fuzz);
		    		if (bitstring != null){
		    			//System.err.println(normaltok+"->"+fuzz);
		    			break;
		    		}
		    	}
		    }
		    
			if (bitstring != null){
				int i;
				bitstring = StringUtils.pad(bitstring, 16).replace(' ', '0');
				for(i=2; i<=16; i+=2){
					pairs.add(t, "BigCluster|" + bitstring.substring(0,i));
				}
				if (t<tokens.size()-1){
					for(i=4; i<=12; i+=4)
						pairs.add(t+1, "PrevBigCluster"+"|" + bitstring.substring(0,i));
				}
				if (t>0){
					for(i=4; i<=12; i+=4)
						pairs.add(t-1, "NextBigCluster"+"|" + bitstring.substring(0,i));
				}
			}
/*				else{
				pairs.add(t, "BigCluster|none");
			}*/
		}
	}
}