gr.eap.LSHDB.GramKey.java Source code

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Here is the source code for gr.eap.LSHDB.GramKey.java

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/*
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package gr.eap.LSHDB;

import gr.eap.LSHDB.embeddables.BloomFilter;
import gr.eap.LSHDB.embeddables.StringEmb;
import java.security.InvalidParameterException;
import java.util.Random;
import org.apache.commons.math3.distribution.BinomialDistribution;
import org.apache.log4j.Logger;

/**
 *
 * @author dimkar
 */
public class GramKey extends Key {
    final static Logger log = Logger.getLogger(GramKey.class);

    public static final long serialVersionUID = 501001L;

    public int t;
    public int q = 2;
    public char padChar;
    public int[][] samples;
    String[] tokens;
    int times;

    public GramKey(String keyFieldName, double delta, int t, int q, char padChar, boolean tokenized,
            boolean performComparisons, Embeddable emb) {
        this.keyFieldName = keyFieldName;
        this.k = k;
        this.delta = delta;
        this.t = t;
        this.q = q;
        this.padChar = padChar;
        optimizeL();
        this.tokenized = tokenized;
        log.info("Number of hash tables generated L=" + this.L + " using k=" + this.k + " and size=" + this.size);

        this.performComparisons = performComparisons;
        //if (emb==null)
        //  throw new StoreInitException("Embeddable object cannot be null.");
        setEmbeddable(emb);
    }

    public GramKey(String keyFieldName) {
        this(keyFieldName, .1, 2, 2, '%', true, true, new StringEmb(2, '%'));
    }

    public GramKey(int k, double delta, int t) {
        this.k = k;
        this.delta = delta;
        this.t = t;
        this.padChar = '%';
        optimizeL();
    }

    public void setTimes(int times) {
        this.times = times;
    }

    @Override
    public int optimizeL() {
        this.L = 1;
        return 1;
    }

    @Override
    public Key create(double thresholdRatio) {
        int t = (int) Math.round(this.t * thresholdRatio);
        return new GramKey(k, delta, t);
    }

}