Search in sources :

Example 1 with CASHInterval

use of de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval in project elki by elki-project.

the class CASH method initHeap.

/**
 * Initializes the heap with the root intervals.
 *
 * @param heap the heap to be initialized
 * @param relation the database storing the parameterization functions
 * @param dim the dimensionality of the database
 * @param ids the ids of the database
 */
private void initHeap(ObjectHeap<IntegerPriorityObject<CASHInterval>> heap, Relation<ParameterizationFunction> relation, int dim, DBIDs ids) {
    CASHIntervalSplit split = new CASHIntervalSplit(relation, minPts);
    // determine minimum and maximum function value of all functions
    double[] minMax = determineMinMaxDistance(relation, dim);
    double d_min = minMax[0], d_max = minMax[1];
    double dIntervalLength = d_max - d_min;
    int numDIntervals = (int) FastMath.ceil(dIntervalLength / jitter);
    double dIntervalSize = dIntervalLength / numDIntervals;
    double[] d_mins = new double[numDIntervals], d_maxs = new double[numDIntervals];
    if (LOG.isVerbose()) {
        LOG.verbose(// 
        new StringBuilder().append("d_min ").append(d_min).append("\nd_max ").append(// 
        d_max).append("\nnumDIntervals ").append(// 
        numDIntervals).append("\ndIntervalSize ").append(dIntervalSize).toString());
    }
    // alpha intervals
    double[] alphaMin = new double[dim - 1], alphaMax = new double[dim - 1];
    Arrays.fill(alphaMax, Math.PI);
    for (int i = 0; i < numDIntervals; i++) {
        d_mins[i] = (i == 0) ? d_min : d_maxs[i - 1];
        d_maxs[i] = (i < numDIntervals - 1) ? d_mins[i] + dIntervalSize : d_max - d_mins[i];
        HyperBoundingBox alphaInterval = new HyperBoundingBox(alphaMin, alphaMax);
        ModifiableDBIDs intervalIDs = split.determineIDs(ids, alphaInterval, d_mins[i], d_maxs[i]);
        if (intervalIDs != null && intervalIDs.size() >= minPts) {
            CASHInterval rootInterval = new CASHInterval(alphaMin, alphaMax, split, intervalIDs, -1, 0, d_mins[i], d_maxs[i]);
            heap.add(new IntegerPriorityObject<>(rootInterval.priority(), rootInterval));
        }
    }
    if (LOG.isDebuggingFiner()) {
        LOG.debugFiner(new StringBuilder().append("heap.size: ").append(heap.size()).toString());
    }
}
Also used : CASHInterval(de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval) CASHIntervalSplit(de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHIntervalSplit) ModifiableDBIDs(de.lmu.ifi.dbs.elki.database.ids.ModifiableDBIDs)

Example 2 with CASHInterval

use of de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval in project elki by elki-project.

the class CASH method doDetermineNextIntervalAtMaxLevel.

/**
 * Recursive helper method to determine the next ''best'' interval at maximum
 * level, i.e. the next interval containing the most unprocessed objects
 *
 * @param heap the heap storing the intervals
 * @return the next ''best'' interval at maximum level
 */
private CASHInterval doDetermineNextIntervalAtMaxLevel(ObjectHeap<IntegerPriorityObject<CASHInterval>> heap) {
    CASHInterval interval = heap.poll().getObject();
    int dim = interval.getDimensionality();
    while (true) {
        // max level is reached
        if (interval.getLevel() >= maxLevel && interval.getMaxSplitDimension() == (dim - 1)) {
            return interval;
        }
        if (heap.size() % 10000 == 0 && LOG.isVerbose()) {
            LOG.verbose("heap size " + heap.size());
        }
        if (heap.size() >= 40000) {
            LOG.warning("Heap size > 40.000! Stopping.");
            heap.clear();
            return null;
        }
        if (LOG.isDebuggingFiner()) {
            LOG.debugFiner("split " + interval.toString() + " " + interval.getLevel() + "-" + interval.getMaxSplitDimension());
        }
        interval.split();
        // noise
        if (!interval.hasChildren()) {
            return null;
        }
        CASHInterval bestInterval;
        if (interval.getLeftChild() != null && interval.getRightChild() != null) {
            int comp = interval.getLeftChild().compareTo(interval.getRightChild());
            if (comp < 0) {
                bestInterval = interval.getRightChild();
                heap.add(new IntegerPriorityObject<>(interval.getLeftChild().priority(), interval.getLeftChild()));
            } else {
                bestInterval = interval.getLeftChild();
                heap.add(new IntegerPriorityObject<>(interval.getRightChild().priority(), interval.getRightChild()));
            }
        } else if (interval.getLeftChild() == null) {
            bestInterval = interval.getRightChild();
        } else {
            bestInterval = interval.getLeftChild();
        }
        interval = bestInterval;
    }
}
Also used : CASHInterval(de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval)

Example 3 with CASHInterval

use of de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval in project elki by elki-project.

the class CASH method doRun.

/**
 * Runs the CASH algorithm on the specified database, this method is
 * recursively called until only noise is left.
 *
 * @param relation the Relation to run the CASH algorithm on
 * @param progress the progress object for verbose messages
 * @return a mapping of subspace dimensionalities to clusters
 */
private Clustering<Model> doRun(Relation<ParameterizationFunction> relation, FiniteProgress progress) {
    Clustering<Model> res = new Clustering<>("CASH clustering", "cash-clustering");
    final int dim = dimensionality(relation);
    // init heap
    ObjectHeap<IntegerPriorityObject<CASHInterval>> heap = new ComparableMinHeap<>();
    ModifiableDBIDs noiseIDs = DBIDUtil.newHashSet(relation.getDBIDs());
    initHeap(heap, relation, dim, noiseIDs);
    if (LOG.isVerbose()) {
        LOG.verbose(new StringBuilder().append("dim ").append(dim).append(" database.size ").append(relation.size()).toString());
    }
    // get the ''best'' d-dimensional intervals at max level
    while (!heap.isEmpty()) {
        CASHInterval interval = determineNextIntervalAtMaxLevel(heap);
        if (LOG.isVerbose()) {
            LOG.verbose("next interval in dim " + dim + ": " + interval);
        }
        // only noise left
        if (interval == null) {
            break;
        }
        // do a dim-1 dimensional run
        ModifiableDBIDs clusterIDs = DBIDUtil.newHashSet();
        if (dim > minDim + 1) {
            ModifiableDBIDs ids;
            double[][] basis_dim_minus_1;
            if (adjust) {
                ids = DBIDUtil.newHashSet();
                basis_dim_minus_1 = runDerivator(relation, dim, interval, ids);
            } else {
                ids = interval.getIDs();
                basis_dim_minus_1 = determineBasis(SpatialUtil.centroid(interval));
            }
            if (ids.size() != 0) {
                MaterializedRelation<ParameterizationFunction> db = buildDB(dim, basis_dim_minus_1, ids, relation);
                // add result of dim-1 to this result
                Clustering<Model> res_dim_minus_1 = doRun(db, progress);
                for (Cluster<Model> cluster : res_dim_minus_1.getAllClusters()) {
                    res.addToplevelCluster(cluster);
                    noiseIDs.removeDBIDs(cluster.getIDs());
                    clusterIDs.addDBIDs(cluster.getIDs());
                    processedIDs.addDBIDs(cluster.getIDs());
                }
            }
        } else // dim == minDim
        {
            LinearEquationSystem les = runDerivator(relation, dim - 1, interval.getIDs());
            Cluster<Model> c = new Cluster<Model>(interval.getIDs(), new LinearEquationModel(les));
            res.addToplevelCluster(c);
            noiseIDs.removeDBIDs(interval.getIDs());
            clusterIDs.addDBIDs(interval.getIDs());
            processedIDs.addDBIDs(interval.getIDs());
        }
        // Rebuild heap
        ArrayList<IntegerPriorityObject<CASHInterval>> heapVector = new ArrayList<>(heap.size());
        for (ObjectHeap.UnsortedIter<IntegerPriorityObject<CASHInterval>> iter = heap.unsortedIter(); iter.valid(); iter.advance()) {
            heapVector.add(iter.get());
        }
        heap.clear();
        for (IntegerPriorityObject<CASHInterval> pair : heapVector) {
            CASHInterval currentInterval = pair.getObject();
            currentInterval.removeIDs(clusterIDs);
            if (currentInterval.getIDs().size() >= minPts) {
                heap.add(new IntegerPriorityObject<>(currentInterval.priority(), currentInterval));
            }
        }
        if (progress != null) {
            progress.setProcessed(processedIDs.size(), LOG);
        }
    }
    // put noise to clusters
    if (!noiseIDs.isEmpty()) {
        if (dim == noiseDim) {
            res.addToplevelCluster(new Cluster<Model>(noiseIDs, true, ClusterModel.CLUSTER));
            processedIDs.addDBIDs(noiseIDs);
        } else if (noiseIDs.size() >= minPts) {
            LinearEquationSystem les = runDerivator(fulldatabase, dim - 1, noiseIDs);
            res.addToplevelCluster(new Cluster<Model>(noiseIDs, true, new LinearEquationModel(les)));
            processedIDs.addDBIDs(noiseIDs);
        }
    }
    if (LOG.isDebugging()) {
        StringBuilder msg = new StringBuilder();
        msg.append("noise fuer dim ").append(dim).append(": ").append(noiseIDs.size());
        for (Cluster<Model> c : res.getAllClusters()) {
            if (c.getModel() instanceof LinearEquationModel) {
                msg.append("\n Cluster: Dim: ").append(((LinearEquationModel) c.getModel()).getLes().subspacedim());
            } else {
                msg.append("\n Cluster: ").append(c.getModel().getClass().getName());
            }
            msg.append(" size: ").append(c.size());
        }
        LOG.debugFine(msg.toString());
    }
    if (progress != null) {
        progress.setProcessed(processedIDs.size(), LOG);
    }
    return res;
}
Also used : CASHInterval(de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval) ComparableMinHeap(de.lmu.ifi.dbs.elki.utilities.datastructures.heap.ComparableMinHeap) ArrayList(java.util.ArrayList) ObjectHeap(de.lmu.ifi.dbs.elki.utilities.datastructures.heap.ObjectHeap) LinearEquationModel(de.lmu.ifi.dbs.elki.data.model.LinearEquationModel) ClusterModel(de.lmu.ifi.dbs.elki.data.model.ClusterModel) Model(de.lmu.ifi.dbs.elki.data.model.Model) IntegerPriorityObject(de.lmu.ifi.dbs.elki.utilities.datastructures.heap.IntegerPriorityObject) ParameterizationFunction(de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.ParameterizationFunction) ModifiableDBIDs(de.lmu.ifi.dbs.elki.database.ids.ModifiableDBIDs) LinearEquationSystem(de.lmu.ifi.dbs.elki.math.linearalgebra.LinearEquationSystem) LinearEquationModel(de.lmu.ifi.dbs.elki.data.model.LinearEquationModel)

Aggregations

CASHInterval (de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHInterval)3 ModifiableDBIDs (de.lmu.ifi.dbs.elki.database.ids.ModifiableDBIDs)2 CASHIntervalSplit (de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.CASHIntervalSplit)1 ParameterizationFunction (de.lmu.ifi.dbs.elki.algorithm.clustering.correlation.cash.ParameterizationFunction)1 ClusterModel (de.lmu.ifi.dbs.elki.data.model.ClusterModel)1 LinearEquationModel (de.lmu.ifi.dbs.elki.data.model.LinearEquationModel)1 Model (de.lmu.ifi.dbs.elki.data.model.Model)1 LinearEquationSystem (de.lmu.ifi.dbs.elki.math.linearalgebra.LinearEquationSystem)1 ComparableMinHeap (de.lmu.ifi.dbs.elki.utilities.datastructures.heap.ComparableMinHeap)1 IntegerPriorityObject (de.lmu.ifi.dbs.elki.utilities.datastructures.heap.IntegerPriorityObject)1 ObjectHeap (de.lmu.ifi.dbs.elki.utilities.datastructures.heap.ObjectHeap)1 ArrayList (java.util.ArrayList)1