Examples with WritableDoubleDataStore de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore used on opensource projects

Example 31 with WritableDoubleDataStore

use of de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore in project elki by elki-project.

the class CTLuZTestOutlier method run.

/**
 * Main method.
 *
 * @param database Database
 * @param nrel Neighborhood relation
 * @param relation Data relation (1d!)
 * @return Outlier detection result
 */
public OutlierResult run(Database database, Relation<N> nrel, Relation<? extends NumberVector> relation) {
    final NeighborSetPredicate npred = getNeighborSetPredicateFactory().instantiate(database, nrel);
    WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
    MeanVariance zmv = new MeanVariance();
    for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
        DBIDs neighbors = npred.getNeighborDBIDs(iditer);
        // Compute Mean of neighborhood
        Mean localmean = new Mean();
        for (DBIDIter iter = neighbors.iter(); iter.valid(); iter.advance()) {
            if (DBIDUtil.equal(iditer, iter)) {
                continue;
            }
            localmean.put(relation.get(iter).doubleValue(0));
        }
        final double localdiff;
        if (localmean.getCount() > 0) {
            localdiff = relation.get(iditer).doubleValue(0) - localmean.getMean();
        } else {
            localdiff = 0.0;
        }
        scores.putDouble(iditer, localdiff);
        zmv.put(localdiff);
    }
    // Normalize scores using mean and variance
    DoubleMinMax minmax = new DoubleMinMax();
    for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
        double score = Math.abs(scores.doubleValue(iditer) - zmv.getMean()) / zmv.getSampleStddev();
        minmax.put(score);
        scores.putDouble(iditer, score);
    }
    // Wrap result
    DoubleRelation scoreResult = new MaterializedDoubleRelation("ZTest", "Z Test score", scores, relation.getDBIDs());
    OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0);
    OutlierResult or = new OutlierResult(scoreMeta, scoreResult);
    or.addChildResult(npred);
    return or;
}

Example 32 with WritableDoubleDataStore

use of de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore in project elki by elki-project.

the class KNNSOS method run.

/**
 * Run the algorithm.
 *
 * @param relation data relation
 * @return outlier detection result
 */
public OutlierResult run(Relation<O> relation) {
    // Query size
    final int k1 = k + 1;
    final double perplexity = k / 3.;
    KNNQuery<O> knnq = relation.getKNNQuery(getDistanceFunction(), k1);
    final double logPerp = FastMath.log(perplexity);
    double[] p = new double[k + 10];
    FiniteProgress prog = LOG.isVerbose() ? new FiniteProgress("KNNSOS scores", relation.size(), LOG) : null;
    WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_DB, 1.);
    for (DBIDIter it = relation.iterDBIDs(); it.valid(); it.advance()) {
        KNNList knns = knnq.getKNNForDBID(it, k1);
        if (p.length < knns.size() + 1) {
            p = new double[knns.size() + 10];
        }
        final DoubleDBIDListIter ki = knns.iter();
        // Compute affinities
        SOS.computePi(it, ki, p, perplexity, logPerp);
        // Normalization factor:
        double s = SOS.sumOfProbabilities(it, ki, p);
        if (s > 0) {
            ISOS.nominateNeighbors(it, ki, p, 1. / s, scores);
        }
        LOG.incrementProcessed(prog);
    }
    LOG.ensureCompleted(prog);
    // Find minimum and maximum.
    DoubleMinMax minmax = ISOS.transformScores(scores, relation.getDBIDs(), logPerp, phi);
    DoubleRelation scoreres = new MaterializedDoubleRelation("kNN Stoachastic Outlier Selection", "knnsos-outlier", scores, relation.getDBIDs());
    OutlierScoreMeta meta = new ProbabilisticOutlierScore(minmax.getMin(), minmax.getMax(), 0.);
    return new OutlierResult(meta, scoreres);
}

Example 33 with WritableDoubleDataStore

use of de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore in project elki by elki-project.

the class COP method run.

/**
 * Process a single relation.
 *
 * @param relation Relation to process
 * @return Outlier detection result
 */
public OutlierResult run(Relation<V> relation) {
    final DBIDs ids = relation.getDBIDs();
    KNNQuery<V> knnQuery = QueryUtil.getKNNQuery(relation, getDistanceFunction(), k + 1);
    final int dim = RelationUtil.dimensionality(relation);
    if (k <= dim + 1) {
        LOG.warning("PCA is underspecified with a too low k! k should be at much larger than " + dim);
    }
    WritableDoubleDataStore cop_score = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_STATIC);
    WritableDataStore<double[]> cop_err_v = null;
    WritableIntegerDataStore cop_dim = null;
    if (models) {
        cop_err_v = DataStoreUtil.makeStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_STATIC, double[].class);
        cop_dim = DataStoreUtil.makeIntegerStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_STATIC, -1);
    }
    // compute neighbors of each db object
    FiniteProgress prog = LOG.isVerbose() ? new FiniteProgress("Correlation Outlier Probabilities", relation.size(), LOG) : null;
    for (DBIDIter id = ids.iter(); id.valid(); id.advance()) {
        KNNList neighbors = knnQuery.getKNNForDBID(id, k + 1);
        ModifiableDBIDs nids = DBIDUtil.newHashSet(neighbors);
        // Do not use query object
        nids.remove(id);
        double[] centroid = Centroid.make(relation, nids).getArrayRef();
        double[] relative = minusEquals(relation.get(id).toArray(), centroid);
        PCAResult pcares = pca.processIds(nids, relation);
        double[][] evecs = pcares.getEigenvectors();
        double[] projected = transposeTimes(evecs, relative);
        double[] evs = pcares.getEigenvalues();
        double min = Double.POSITIVE_INFINITY;
        int vdim = dim;
        switch(dist) {
            case CHISQUARED:
                {
                    double sqdevs = 0;
                    for (int d = 0; d < dim; d++) {
                        // Scale with Stddev
                        double dev = projected[d];
                        // Accumulate
                        sqdevs += dev * dev / evs[d];
                        // Evaluate
                        double score = 1 - ChiSquaredDistribution.cdf(sqdevs, d + 1);
                        if (score < min) {
                            min = score;
                            vdim = d + 1;
                        }
                    }
                    break;
                }
            case GAMMA:
                {
                    double[][] dists = new double[dim][nids.size()];
                    int j = 0;
                    double[] srel = new double[dim];
                    for (DBIDIter s = nids.iter(); s.valid() && j < nids.size(); s.advance()) {
                        V vec = relation.get(s);
                        for (int d = 0; d < dim; d++) {
                            srel[d] = vec.doubleValue(d) - centroid[d];
                        }
                        double[] serr = transposeTimes(evecs, srel);
                        double sqdist = 0.0;
                        for (int d = 0; d < dim; d++) {
                            double serrd = serr[d];
                            sqdist += serrd * serrd / evs[d];
                            dists[d][j] = sqdist;
                        }
                        j++;
                    }
                    double sqdevs = 0;
                    for (int d = 0; d < dim; d++) {
                        // Scale with Stddev
                        final double dev = projected[d];
                        // Accumulate
                        sqdevs += dev * dev / evs[d];
                        // Sort, so we can trim the top 15% below.
                        Arrays.sort(dists[d]);
                        // Evaluate
                        double score = 1 - GammaChoiWetteEstimator.STATIC.estimate(dists[d], SHORTENED_ARRAY).cdf(sqdevs);
                        if (score < min) {
                            min = score;
                            vdim = d + 1;
                        }
                    }
                    break;
                }
        }
        // Normalize the value
        final double prob = expect * (1 - min) / (expect + min);
        // Construct the error vector:
        for (int d = vdim; d < dim; d++) {
            projected[d] = 0.;
        }
        double[] ev = timesEquals(times(evecs, projected), -1 * prob);
        cop_score.putDouble(id, prob);
        if (models) {
            cop_err_v.put(id, ev);
            cop_dim.putInt(id, dim + 1 - vdim);
        }
        LOG.incrementProcessed(prog);
    }
    LOG.ensureCompleted(prog);
    // combine results.
    DoubleRelation scoreResult = new MaterializedDoubleRelation("Correlation Outlier Probabilities", COP_SCORES, cop_score, ids);
    OutlierScoreMeta scoreMeta = new ProbabilisticOutlierScore();
    OutlierResult result = new OutlierResult(scoreMeta, scoreResult);
    if (models) {
        result.addChildResult(new MaterializedRelation<>("Local Dimensionality", COP_DIM, TypeUtil.INTEGER, cop_dim, ids));
        result.addChildResult(new MaterializedRelation<>("Error vectors", COP_ERRORVEC, TypeUtil.DOUBLE_ARRAY, cop_err_v, ids));
    }
    return result;
}

Example 34 with WritableDoubleDataStore

use of de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore in project elki by elki-project.

the class EMOutlier method run.

/**
 * Runs the algorithm in the timed evaluation part.
 *
 * @param database Database to process
 * @param relation Relation to process
 * @return Outlier result
 */
public OutlierResult run(Database database, Relation<V> relation) {
    emClustering.setSoft(true);
    Clustering<?> emresult = emClustering.run(database, relation);
    Relation<double[]> soft = null;
    for (It<Relation<double[]>> iter = emresult.getHierarchy().iterChildren(emresult).filter(Relation.class); iter.valid(); iter.advance()) {
        if (iter.get().getDataTypeInformation() == EM.SOFT_TYPE) {
            soft = iter.get();
        }
    }
    double globmax = 0.0;
    WritableDoubleDataStore emo_score = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_TEMP | DataStoreFactory.HINT_HOT);
    for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
        double maxProb = Double.POSITIVE_INFINITY;
        double[] probs = soft.get(iditer);
        for (double prob : probs) {
            maxProb = Math.min(1. - prob, maxProb);
        }
        emo_score.putDouble(iditer, maxProb);
        globmax = Math.max(maxProb, globmax);
    }
    DoubleRelation scoreres = new MaterializedDoubleRelation("EM outlier scores", "em-outlier", emo_score, relation.getDBIDs());
    OutlierScoreMeta meta = new ProbabilisticOutlierScore(0.0, globmax);
    // combine results.
    OutlierResult result = new OutlierResult(meta, scoreres);
    // TODO: add a keep-EM flag?
    result.addChildResult(emresult);
    return result;
}

Example 35 with WritableDoubleDataStore

use of de.lmu.ifi.dbs.elki.database.datastore.WritableDoubleDataStore in project elki by elki-project.

the class SilhouetteOutlierDetection method run.

@Override
public OutlierResult run(Database database) {
    Relation<O> relation = database.getRelation(getDistanceFunction().getInputTypeRestriction());
    DistanceQuery<O> dq = database.getDistanceQuery(relation, getDistanceFunction());
    // TODO: improve ELKI api to ensure we're using the same DBIDs!
    Clustering<?> c = clusterer.run(database);
    WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_DB);
    DoubleMinMax mm = new DoubleMinMax();
    List<? extends Cluster<?>> clusters = c.getAllClusters();
    for (Cluster<?> cluster : clusters) {
        if (cluster.size() <= 1 || cluster.isNoise()) {
            switch(noiseOption) {
                case IGNORE_NOISE:
                case TREAT_NOISE_AS_SINGLETONS:
                    // As suggested in Rousseeuw, we use 0 for singletons.
                    for (DBIDIter iter = cluster.getIDs().iter(); iter.valid(); iter.advance()) {
                        scores.put(iter, 0.);
                    }
                    mm.put(0.);
                    continue;
                case MERGE_NOISE:
                    // Treat as cluster below
                    break;
            }
        }
        ArrayDBIDs ids = DBIDUtil.ensureArray(cluster.getIDs());
        // temporary storage.
        double[] as = new double[ids.size()];
        DBIDArrayIter it1 = ids.iter(), it2 = ids.iter();
        for (it1.seek(0); it1.valid(); it1.advance()) {
            // a: In-cluster distances
            // Already computed distances
            double a = as[it1.getOffset()];
            for (it2.seek(it1.getOffset() + 1); it2.valid(); it2.advance()) {
                final double dist = dq.distance(it1, it2);
                a += dist;
                as[it2.getOffset()] += dist;
            }
            a /= (ids.size() - 1);
            // b: other clusters:
            double min = Double.POSITIVE_INFINITY;
            for (Cluster<?> ocluster : clusters) {
                if (ocluster == /* yes, reference identity */
                cluster) {
                    continue;
                }
                if (ocluster.isNoise()) {
                    switch(noiseOption) {
                        case IGNORE_NOISE:
                            continue;
                        case MERGE_NOISE:
                            // No special treatment
                            break;
                        case TREAT_NOISE_AS_SINGLETONS:
                            // Treat noise cluster as singletons:
                            for (DBIDIter it3 = ocluster.getIDs().iter(); it3.valid(); it3.advance()) {
                                double dist = dq.distance(it1, it3);
                                if (dist < min) {
                                    min = dist;
                                }
                            }
                            continue;
                    }
                }
                final DBIDs oids = ocluster.getIDs();
                double b = 0.;
                for (DBIDIter it3 = oids.iter(); it3.valid(); it3.advance()) {
                    b += dq.distance(it1, it3);
                }
                b /= oids.size();
                if (b < min) {
                    min = b;
                }
            }
            final double score = (min - a) / Math.max(min, a);
            scores.put(it1, score);
            mm.put(score);
        }
    }
    // Build result representation.
    DoubleRelation scoreResult = new MaterializedDoubleRelation("Silhouette Coefficients", "silhouette-outlier", scores, relation.getDBIDs());
    OutlierScoreMeta scoreMeta = new InvertedOutlierScoreMeta(mm.getMin(), mm.getMax(), -1., 1., .5);
    return new OutlierResult(scoreMeta, scoreResult);
}