use of de.lmu.ifi.dbs.elki.database.relation.DoubleRelation in project elki by elki-project.
the class CTLuMoranScatterplotOutlier 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);
// Compute the global mean and variance
MeanVariance globalmv = new MeanVariance();
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
globalmv.put(relation.get(iditer).doubleValue(0));
}
DoubleMinMax minmax = new DoubleMinMax();
WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
// calculate neighborhood average of normalized attribute values.
for (DBIDIter iditer = relation.iterDBIDs(); iditer.valid(); iditer.advance()) {
// Compute global z score
final double globalZ = (relation.get(iditer).doubleValue(0) - globalmv.getMean()) / globalmv.getNaiveStddev();
// Compute local average z score
Mean localm = new Mean();
for (DBIDIter iter = npred.getNeighborDBIDs(iditer).iter(); iter.valid(); iter.advance()) {
if (DBIDUtil.equal(iditer, iter)) {
continue;
}
localm.put((relation.get(iter).doubleValue(0) - globalmv.getMean()) / globalmv.getNaiveStddev());
}
// if neighors.size == 0
final double localZ;
if (localm.getCount() > 0) {
localZ = localm.getMean();
} else {
// if s has no neighbors => Wzi = zi
localZ = globalZ;
}
// compute score
// Note: in the original moran scatterplot, any object with a score < 0 would be an outlier.
final double score = Math.max(-globalZ * localZ, 0);
minmax.put(score);
scores.putDouble(iditer, score);
}
DoubleRelation scoreResult = new MaterializedDoubleRelation("MoranOutlier", "Moran Scatterplot Outlier", scores, relation.getDBIDs());
OutlierScoreMeta scoreMeta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY, 0);
OutlierResult or = new OutlierResult(scoreMeta, scoreResult);
or.addChildResult(npred);
return or;
}
use of de.lmu.ifi.dbs.elki.database.relation.DoubleRelation in project elki by elki-project.
the class ParallelSimplifiedLOF method run.
public OutlierResult run(Database database, Relation<O> relation) {
DBIDs ids = relation.getDBIDs();
DistanceQuery<O> distq = database.getDistanceQuery(relation, getDistanceFunction());
KNNQuery<O> knnq = database.getKNNQuery(distq, k + 1);
// Phase one: KNN and k-dist
WritableDataStore<KNNList> knns = DataStoreUtil.makeStorage(ids, DataStoreFactory.HINT_DB, KNNList.class);
{
// Compute kNN
KNNProcessor<O> knnm = new KNNProcessor<>(k + 1, knnq);
SharedObject<KNNList> knnv = new SharedObject<>();
WriteDataStoreProcessor<KNNList> storek = new WriteDataStoreProcessor<>(knns);
knnm.connectKNNOutput(knnv);
storek.connectInput(knnv);
ParallelExecutor.run(ids, knnm, storek);
}
// Phase two: simplified-lrd
WritableDoubleDataStore lrds = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_DB);
{
SimplifiedLRDProcessor lrdm = new SimplifiedLRDProcessor(knns);
SharedDouble lrdv = new SharedDouble();
WriteDoubleDataStoreProcessor storelrd = new WriteDoubleDataStoreProcessor(lrds);
lrdm.connectOutput(lrdv);
storelrd.connectInput(lrdv);
ParallelExecutor.run(ids, lrdm, storelrd);
}
// Phase three: Simplified-LOF
WritableDoubleDataStore lofs = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_DB);
DoubleMinMax minmax;
{
LOFProcessor lofm = new LOFProcessor(knns, lrds, true);
SharedDouble lofv = new SharedDouble();
DoubleMinMaxProcessor mmm = new DoubleMinMaxProcessor();
WriteDoubleDataStoreProcessor storelof = new WriteDoubleDataStoreProcessor(lofs);
lofm.connectOutput(lofv);
mmm.connectInput(lofv);
storelof.connectInput(lofv);
ParallelExecutor.run(ids, lofm, storelof, mmm);
minmax = mmm.getMinMax();
}
DoubleRelation scoreres = new MaterializedDoubleRelation("Simplified Local Outlier Factor", "simplified-lof-outlier", lofs, ids);
OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 1.0);
return new OutlierResult(meta, scoreres);
}
use of de.lmu.ifi.dbs.elki.database.relation.DoubleRelation in project elki by elki-project.
the class FeatureBagging method run.
/**
* Run the algorithm on a data set.
*
* @param database Database context
* @param relation Relation to use
* @return Outlier detection result
*/
public OutlierResult run(Database database, Relation<NumberVector> relation) {
final int dbdim = RelationUtil.dimensionality(relation);
final int mindim = dbdim >> 1;
final int maxdim = dbdim - 1;
final Random rand = rnd.getSingleThreadedRandom();
ArrayList<OutlierResult> results = new ArrayList<>(num);
{
FiniteProgress prog = LOG.isVerbose() ? new FiniteProgress("LOF iterations", num, LOG) : null;
for (int i = 0; i < num; i++) {
long[] dimset = randomSubspace(dbdim, mindim, maxdim, rand);
SubspaceEuclideanDistanceFunction df = new SubspaceEuclideanDistanceFunction(dimset);
LOF<NumberVector> lof = new LOF<>(k, df);
// run LOF and collect the result
OutlierResult result = lof.run(database, relation);
results.add(result);
LOG.incrementProcessed(prog);
}
LOG.ensureCompleted(prog);
}
WritableDoubleDataStore scores = DataStoreUtil.makeDoubleStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC);
DoubleMinMax minmax = new DoubleMinMax();
if (breadth) {
FiniteProgress cprog = LOG.isVerbose() ? new FiniteProgress("Combining results", relation.size(), LOG) : null;
@SuppressWarnings("unchecked") Pair<DBIDIter, DoubleRelation>[] IDVectorOntoScoreVector = (Pair<DBIDIter, DoubleRelation>[]) new Pair[results.size()];
// Mapping score-sorted DBID-Iterators onto their corresponding scores.
// We need to initialize them now be able to iterate them "in parallel".
{
int i = 0;
for (OutlierResult r : results) {
IDVectorOntoScoreVector[i] = new Pair<DBIDIter, DoubleRelation>(r.getOrdering().order(relation.getDBIDs()).iter(), r.getScores());
i++;
}
}
// Iterating over the *lines* of the AS_t(i)-matrix.
for (int i = 0; i < relation.size(); i++) {
// Iterating over the elements of a line (breadth-first).
for (Pair<DBIDIter, DoubleRelation> pair : IDVectorOntoScoreVector) {
DBIDIter iter = pair.first;
// for every DBID).
if (iter.valid()) {
double score = pair.second.doubleValue(iter);
if (Double.isNaN(scores.doubleValue(iter))) {
scores.putDouble(iter, score);
minmax.put(score);
}
iter.advance();
} else {
LOG.warning("Incomplete result: Iterator does not contain |DB| DBIDs");
}
}
// Progress does not take the initial mapping into account.
LOG.incrementProcessed(cprog);
}
LOG.ensureCompleted(cprog);
} else {
FiniteProgress cprog = LOG.isVerbose() ? new FiniteProgress("Combining results", relation.size(), LOG) : null;
for (DBIDIter iter = relation.iterDBIDs(); iter.valid(); iter.advance()) {
double sum = 0.0;
for (OutlierResult r : results) {
final double s = r.getScores().doubleValue(iter);
if (!Double.isNaN(s)) {
sum += s;
}
}
scores.putDouble(iter, sum);
minmax.put(sum);
LOG.incrementProcessed(cprog);
}
LOG.ensureCompleted(cprog);
}
OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax());
DoubleRelation scoreres = new MaterializedDoubleRelation("Feature bagging", "fb-outlier", scores, relation.getDBIDs());
return new OutlierResult(meta, scoreres);
}
use of de.lmu.ifi.dbs.elki.database.relation.DoubleRelation in project elki by elki-project.
the class RescaleMetaOutlierAlgorithm method run.
@Override
public OutlierResult run(Database database) {
Result innerresult = algorithm.run(database);
OutlierResult or = getOutlierResult(database.getHierarchy(), innerresult);
final DoubleRelation scores = or.getScores();
if (scaling instanceof OutlierScalingFunction) {
((OutlierScalingFunction) scaling).prepare(or);
}
WritableDoubleDataStore scaledscores = DataStoreUtil.makeDoubleStorage(scores.getDBIDs(), DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_STATIC);
DoubleMinMax minmax = new DoubleMinMax();
for (DBIDIter iditer = scores.iterDBIDs(); iditer.valid(); iditer.advance()) {
double val = scaling.getScaled(scores.doubleValue(iditer));
scaledscores.putDouble(iditer, val);
minmax.put(val);
}
OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), scaling.getMin(), scaling.getMax());
DoubleRelation scoresult = new MaterializedDoubleRelation("Scaled Outlier", "scaled-outlier", scaledscores, scores.getDBIDs());
OutlierResult result = new OutlierResult(meta, scoresult);
result.addChildResult(innerresult);
return result;
}
use of de.lmu.ifi.dbs.elki.database.relation.DoubleRelation in project elki by elki-project.
the class SimpleKernelDensityLOF method run.
/**
* Run the naive kernel density LOF algorithm.
*
* @param database Database to query
* @param relation Data to process
* @return LOF outlier result
*/
public OutlierResult run(Database database, Relation<O> relation) {
StepProgress stepprog = LOG.isVerbose() ? new StepProgress("KernelDensityLOF", 3) : null;
final int dim = RelationUtil.dimensionality(relation);
DBIDs ids = relation.getDBIDs();
LOG.beginStep(stepprog, 1, "Materializing neighborhoods w.r.t. distance function.");
KNNQuery<O> knnq = DatabaseUtil.precomputedKNNQuery(database, relation, getDistanceFunction(), k);
// Compute LRDs
LOG.beginStep(stepprog, 2, "Computing densities.");
WritableDoubleDataStore dens = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_HOT | DataStoreFactory.HINT_TEMP);
FiniteProgress densProgress = LOG.isVerbose() ? new FiniteProgress("Densities", ids.size(), LOG) : null;
for (DBIDIter it = ids.iter(); it.valid(); it.advance()) {
final KNNList neighbors = knnq.getKNNForDBID(it, k);
int count = 0;
double sum = 0.0;
// Fast version for double distances
for (DoubleDBIDListIter neighbor = neighbors.iter(); neighbor.valid(); neighbor.advance()) {
if (DBIDUtil.equal(neighbor, it)) {
continue;
}
double max = knnq.getKNNForDBID(neighbor, k).getKNNDistance();
if (max == 0) {
sum = Double.POSITIVE_INFINITY;
break;
}
final double v = neighbor.doubleValue() / max;
sum += kernel.density(v) / MathUtil.powi(max, dim);
count++;
}
final double density = count > 0 ? sum / count : 0.;
dens.putDouble(it, density);
LOG.incrementProcessed(densProgress);
}
LOG.ensureCompleted(densProgress);
// compute LOF_SCORE of each db object
LOG.beginStep(stepprog, 3, "Computing KLOFs.");
WritableDoubleDataStore lofs = DataStoreUtil.makeDoubleStorage(ids, DataStoreFactory.HINT_STATIC);
// track the maximum value for normalization.
DoubleMinMax lofminmax = new DoubleMinMax();
FiniteProgress progressLOFs = LOG.isVerbose() ? new FiniteProgress("KLOF_SCORE for objects", ids.size(), LOG) : null;
for (DBIDIter it = ids.iter(); it.valid(); it.advance()) {
final double lrdp = dens.doubleValue(it);
final double lof;
if (lrdp > 0) {
final KNNList neighbors = knnq.getKNNForDBID(it, k);
double sum = 0.0;
int count = 0;
for (DBIDIter neighbor = neighbors.iter(); neighbor.valid(); neighbor.advance()) {
// skip the point itself
if (DBIDUtil.equal(neighbor, it)) {
continue;
}
sum += dens.doubleValue(neighbor);
count++;
}
lof = (lrdp == Double.POSITIVE_INFINITY) ? (sum == Double.POSITIVE_INFINITY ? 1 : 0.) : sum / (count * lrdp);
} else {
lof = 1.0;
}
lofs.putDouble(it, lof);
// update minimum and maximum
lofminmax.put(lof);
LOG.incrementProcessed(progressLOFs);
}
LOG.ensureCompleted(progressLOFs);
LOG.setCompleted(stepprog);
// Build result representation.
DoubleRelation scoreResult = new MaterializedDoubleRelation("Kernel Density Local Outlier Factor", "kernel-density-slof-outlier", lofs, ids);
OutlierScoreMeta scoreMeta = new QuotientOutlierScoreMeta(lofminmax.getMin(), lofminmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 1.0);
OutlierResult result = new OutlierResult(scoreMeta, scoreResult);
return result;
}
Aggregations