Examples with ClassLabel de.lmu.ifi.dbs.elki.data.ClassLabel used on opensource projects

Example 11 with ClassLabel

use of de.lmu.ifi.dbs.elki.data.ClassLabel in project elki by elki-project.

the class LinearDiscriminantAnalysisFilter method computeProjectionMatrix.

@Override
protected double[][] computeProjectionMatrix(List<V> vectorcolumn, List<? extends ClassLabel> classcolumn, int dim) {
    Map<ClassLabel, IntList> classes = partition(classcolumn);
    // Fix indexing of classes:
    List<ClassLabel> keys = new ArrayList<>(classes.keySet());
    // Compute centroids:
    List<Centroid> centroids = computeCentroids(dim, vectorcolumn, keys, classes);
    final double[][] sigmaB, sigmaI;
    // Between classes covariance:
    {
        CovarianceMatrix covmake = new CovarianceMatrix(dim);
        for (Centroid c : centroids) {
            covmake.put(c);
        }
        sigmaB = covmake.destroyToSampleMatrix();
    }
    {
        // (Average) within class variance:
        CovarianceMatrix covmake = new CovarianceMatrix(dim);
        int numc = keys.size();
        for (int i = 0; i < numc; i++) {
            double[] c = centroids.get(i).getArrayRef();
            // TODO: different weighting strategies? Sampling?
            for (IntIterator it = classes.get(keys.get(i)).iterator(); it.hasNext(); ) {
                covmake.put(minusEquals(vectorcolumn.get(it.nextInt()).toArray(), c));
            }
        }
        sigmaI = covmake.destroyToSampleMatrix();
        if (new LUDecomposition(sigmaI).det() == 0) {
            for (int i = 0; i < dim; i++) {
                sigmaI[i][i] += 1e-10;
            }
        }
    }
    double[][] sol = times(inverse(sigmaI), sigmaB);
    EigenvalueDecomposition decomp = new EigenvalueDecomposition(sol);
    SortedEigenPairs sorted = new SortedEigenPairs(decomp, false);
    return transpose(sorted.eigenVectors(tdim));
}

Example 12 with ClassLabel

use of de.lmu.ifi.dbs.elki.data.ClassLabel in project elki by elki-project.

the class ClassLabelFilter method filter.

@Override
public MultipleObjectsBundle filter(MultipleObjectsBundle objects) {
    MultipleObjectsBundle bundle = new MultipleObjectsBundle();
    // Find a labellist column
    boolean done = false;
    boolean keeplabelcol = false;
    for (int i = 0; i < objects.metaLength(); i++) {
        SimpleTypeInformation<?> meta = objects.meta(i);
        // Skip non-labellist columns - or if we already had a labellist
        if (done || !LabelList.class.equals(meta.getRestrictionClass())) {
            bundle.appendColumn(meta, objects.getColumn(i));
            continue;
        }
        done = true;
        // We split the label column into two parts
        List<ClassLabel> clscol = new ArrayList<>(objects.dataLength());
        List<LabelList> lblcol = new ArrayList<>(objects.dataLength());
        ArrayList<String> lbuf = new ArrayList<>();
        // Split the column
        for (Object obj : objects.getColumn(i)) {
            if (obj != null) {
                LabelList ll = (LabelList) obj;
                int off = (classLabelIndex >= 0) ? classLabelIndex : (ll.size() - classLabelIndex);
                try {
                    ClassLabel lbl = classLabelFactory.makeFromString(ll.get(off));
                    clscol.add(lbl);
                } catch (Exception e) {
                    throw new AbortException("Cannot initialize class labels: " + e.getMessage(), e);
                }
                lbuf.clear();
                for (int j = 0; j < ll.size(); j++) {
                    if (j == off) {
                        continue;
                    }
                    lbuf.add(ll.get(j));
                }
                lblcol.add(LabelList.make(lbuf));
                if (!lbuf.isEmpty()) {
                    keeplabelcol = true;
                }
            } else {
                clscol.add(null);
                lblcol.add(null);
            }
        }
        bundle.appendColumn(classLabelFactory.getTypeInformation(), clscol);
        // Only add the label column when it's not empty.
        if (keeplabelcol) {
            bundle.appendColumn(meta, lblcol);
        }
    }
    return bundle;
}