fullngram.java

Boosting算法软件包

package jboost.examples.ngram;

import java.util.Arrays;

/**
 * Full ngrams are all ngrams up to a given length.
 *
 * @author Rob Schapire (rewritten by Aaron Arvey)
 */

public class FullNgram extends AbstractNgram {

    /** current ngram length */
    private int n = 1;     
    
    /** window size */
    private int size;

    /**
     * Constructor.  The ngrams will be constructed from the
     * string s and will have length up to the given size.
     * @param s string from which ngrams are constructed
     * @param n maximum size of all ngrams returned
     */
    public FullNgram(String s, int size) {
	super(s);
	this.size = size;
	boolean[] pat = new boolean[] {true};
	enumer = new PatternNgram(words, pat);
    }


    public boolean hasMoreElements() {
	if (n > size)
	    return false;
	n += 1;
	while (!enumer.hasMoreElements() && n <= size) {
	    boolean[] pat = new boolean[n];
	    Arrays.fill(pat, true);
	    enumer = new PatternNgram(words, pat);
	    n += 1;
	}
	return (n <= size);
    }

}