/**
* Select or deselect a column.
*
* @param cnum Column to select
* @param set Value to set
*/
protected void selectColumn(int cnum, boolean set) {
if (set) {
BitsUtil.setI(cols, cnum);
colcard++;
} else {
BitsUtil.clearI(cols, cnum);
colcard--;
}
}
/**
* Select or deselect a row.
*
* @param rnum Row to select
* @param set Value to set
*/
protected void selectRow(int rnum, boolean set) {
if (set) {
BitsUtil.setI(rows, rnum);
rowcard++;
} else {
BitsUtil.clearI(rows, rnum);
rowcard--;
}
}
/**
* Main loop of OUTRES. Run for each object
*
* @param s start dimension
* @param subspace Current subspace
* @param id Current object ID
* @param kernel Kernel
* @return Score
*/
public double outresScore(
final int s, long[] subspace, DBIDRef id, KernelDensityEstimator kernel) {
double score = 1.0; // Initial score is 1.0
final SubspaceEuclideanDistanceFunction df = new SubspaceEuclideanDistanceFunction(subspace);
MeanVariance meanv = new MeanVariance();
for (int i = s; i < kernel.dim; i++) {
if (BitsUtil.get(subspace, i)) { // TODO: needed? Or should we always start
// with i=0?
continue;
}
BitsUtil.setI(subspace, i);
df.setSelectedDimensions(subspace);
final double adjustedEps = kernel.adjustedEps(kernel.dim);
// Query with a larger window, to also get neighbors of neighbors
// Subspace euclidean is metric!
final double range = adjustedEps * 2.;
RangeQuery<V> rq = QueryUtil.getRangeQuery(kernel.relation, df, range);
DoubleDBIDList neighc = rq.getRangeForDBID(id, range);
DoubleDBIDList neigh = refineRange(neighc, adjustedEps);
if (neigh.size() > 2) {
// Relevance test
if (relevantSubspace(subspace, neigh, kernel)) {
final double density = kernel.subspaceDensity(subspace, neigh);
// Compute mean and standard deviation for densities of neighbors.
meanv.reset();
for (DoubleDBIDListIter neighbor = neigh.iter(); neighbor.valid(); neighbor.advance()) {
DoubleDBIDList n2 = subsetNeighborhoodQuery(neighc, neighbor, df, adjustedEps, kernel);
meanv.put(kernel.subspaceDensity(subspace, n2));
}
final double deviation = (meanv.getMean() - density) / (2. * meanv.getSampleStddev());
// High deviation:
if (deviation >= 1) {
score *= (density / deviation);
}
// Recursion
score *= outresScore(i + 1, subspace, id, kernel);
}
}
BitsUtil.clearI(subspace, i);
}
return score;
}