lu.lippmann.cdb.lab.timeseries.WekaTimeSeriesSimilarityUtil.java Source code

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Here is the source code for lu.lippmann.cdb.lab.timeseries.WekaTimeSeriesSimilarityUtil.java

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/**
 * Copyright 2014-2016 LIST (Luxembourg Institute of Science and Technology), all right reserved.
 * Authorship : Olivier PARISOT, Yoanne DIDRY
 * Licensed under GNU General Public License version 3
 */
package lu.lippmann.cdb.lab.timeseries;

import java.util.*;
import java.util.concurrent.*;

import lu.lippmann.cdb.weka.WekaDataProcessingUtil;
import weka.core.*;

/**
 * WekaTimeSeriesSimilarityUtil.
 * 
 * @author Olivier PARISOT
 */
public final class WekaTimeSeriesSimilarityUtil {
    //
    // Static fields
    //

    /** */
    private static final ExecutorService EXECUTOR_SERVICE = Executors
            .newFixedThreadPool(Math.max(2, Math.max(1, Runtime.getRuntime().availableProcessors() - 1)));

    //
    // Constructors
    //

    /**
     * Private constructor.
     */
    private WekaTimeSeriesSimilarityUtil() {
    }

    //
    // Static methods
    //

    public static String findMostSimilarTimeSerie(final Instances testds, final Attribute attr,
            final List<String> attrNames, final boolean THREADED_NN_LOOKUP) {
        //System.out.println("findMostSimilarTimeSerie: for "+attr.name()+" in "+attrNames);

        //System.out.println("findMostSimilarTimeSerie: (before) rows -> "+testds.numInstances());
        final List<String> attrNamesWithCurrent = new ArrayList<>(attrNames);
        attrNamesWithCurrent.add(attr.name());
        final Instances reducedds = WekaDataProcessingUtil.buildDataSetWithoutRowsWithMissingValues(testds,
                attrNamesWithCurrent); // TODO: optimize remove into this method
        //System.out.println(reducedds.numAttributes());
        //System.out.println("findMostSimilarTimeSerie: (after) rows -> "+reducedds.numInstances());
        final double[] startArray1 = reducedds.attributeToDoubleArray(reducedds.attribute(attr.name()).index());
        if (startArray1.length == 0)
            System.out.println("no val for " + attr.name() + "??");

        double min = Double.POSITIVE_INFINITY;
        int idx = -1;

        if (!THREADED_NN_LOOKUP) {
            for (int i = 0; i < reducedds.numAttributes(); i++) {
                //System.out.println(i);
                if (!attrNames.contains(reducedds.attribute(i).name())) {
                    //System.out.println(reducedds.attribute(i).name()+" not in "+attrNames);
                    continue;
                }
                final double[] startArray2 = reducedds.attributeToDoubleArray(i);
                final double distance = new DynamicTimeWarping(startArray1, startArray2).getDistance();
                if (distance < min) {
                    min = distance;
                    idx = i;
                }
                //System.out.println("\t to "+reducedds.attribute(i).name()+": "+distance);
            }
        } else {
            final List<Callable<Object[]>> tasks = new ArrayList<Callable<Object[]>>();
            for (int i = 0; i < reducedds.numAttributes(); i++) {
                if (!attrNames.contains(reducedds.attribute(i).name()))
                    continue;
                final int ii = i;
                tasks.add(new Callable<Object[]>() {
                    @Override
                    public Object[] call() throws Exception {
                        final double[] startArray2 = reducedds.attributeToDoubleArray(ii);
                        final double distance = new DynamicTimeWarping(startArray1, startArray2).getDistance();
                        //System.out.println("\t to "+reducedds.attribute(ii).name()+": "+distance);
                        return new Object[] { distance, ii };
                    }
                });
            }

            try {
                final List<Future<Object[]>> res = EXECUTOR_SERVICE.invokeAll(tasks);
                for (final Future<Object[]> r : res) {
                    final Object[] oo = r.get();
                    final double distance = (Double) oo[0];
                    final int curridx = (Integer) oo[1];
                    if (distance < min) {
                        min = distance;
                        idx = curridx;
                    }
                }
            } catch (Exception e1) {
                e1.printStackTrace();
            }
        }

        final String foundSerie = (idx != -1) ? reducedds.attribute(idx).name() : null;
        //System.out.println("found -> "+foundSerie);
        return foundSerie;
    }
}