summaryrefslogtreecommitdiff
path: root/src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java
diff options
context:
space:
mode:
Diffstat (limited to 'src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java')
-rw-r--r--src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java161
1 files changed, 161 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java b/src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java
new file mode 100644
index 00000000..01df56ae
--- /dev/null
+++ b/src/de/lmu/ifi/dbs/elki/algorithm/clustering/kmeans/initialization/PredefinedInitialMeans.java
@@ -0,0 +1,161 @@
+package de.lmu.ifi.dbs.elki.algorithm.clustering.kmeans.initialization;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2014
+ Ludwig-Maximilians-Universität München
+ Lehr- und Forschungseinheit für Datenbanksysteme
+ ELKI Development Team
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import java.util.ArrayList;
+import java.util.List;
+
+import de.lmu.ifi.dbs.elki.data.Cluster;
+import de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.data.NumberVector.Factory;
+import de.lmu.ifi.dbs.elki.data.model.MeanModel;
+import de.lmu.ifi.dbs.elki.database.Database;
+import de.lmu.ifi.dbs.elki.database.relation.Relation;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.PrimitiveDistanceFunction;
+import de.lmu.ifi.dbs.elki.math.linearalgebra.Vector;
+import de.lmu.ifi.dbs.elki.utilities.exceptions.AbortException;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.VectorListParameter;
+
+/**
+ * Run k-means with prespecified initial means.
+ *
+ * @author Erich Schubert
+ */
+public class PredefinedInitialMeans extends AbstractKMeansInitialization<NumberVector> {
+ /**
+ * Initial means to return.
+ */
+ List<? extends NumberVector> initialMeans;
+
+ /**
+ * Constructor.
+ *
+ * @param initialMeans Initial means
+ */
+ public PredefinedInitialMeans(List<? extends NumberVector> initialMeans) {
+ super(null);
+ this.setInitialMeans(initialMeans);
+ }
+
+ /**
+ * Constructor.
+ *
+ * @param initialMeans Initial means
+ */
+ public PredefinedInitialMeans(double[][] initialMeans) {
+ super(null);
+ this.setInitialMeans(initialMeans);
+ }
+
+ /**
+ * Set the initial means.
+ *
+ * Important notice: Use with care - the means are <em>not copied</em>!
+ *
+ * @param initialMeans initial means.
+ */
+ public void setInitialMeans(List<? extends NumberVector> initialMeans) {
+ this.initialMeans = initialMeans;
+ }
+
+ /**
+ * Set the initial means.
+ *
+ * Important notice: Use with care - the means are <em>not copied</em>!
+ *
+ * @param initialMeans initial means.
+ */
+ public void setInitialClusters(List<? extends Cluster<? extends MeanModel>> initialMeans) {
+ List<Vector> vecs = new ArrayList<>(initialMeans.size());
+ for(Cluster<? extends MeanModel> cluster : initialMeans) {
+ vecs.add(cluster.getModel().getMean().copy());
+ }
+ this.initialMeans = vecs;
+ }
+
+ /**
+ * Set the initial means.
+ *
+ * Important notice: Use with care - the means are <em>not copied</em>!
+ *
+ * @param initialMeans initial means.
+ */
+ public void setInitialMeans(double[][] initialMeans) {
+ List<Vector> vecs = new ArrayList<>(initialMeans.length);
+ for(int i = 0; i < initialMeans.length; ++i) {
+ vecs.add(new Vector(initialMeans[i]));
+ }
+ this.initialMeans = vecs;
+ }
+
+ @Override
+ public <T extends NumberVector, O extends NumberVector> List<O> chooseInitialMeans(Database database, Relation<T> relation, int k, PrimitiveDistanceFunction<? super T> distanceFunction, Factory<O> factory) {
+ if(k != initialMeans.size()) {
+ throw new AbortException("Predefined initial means contained " + initialMeans.size() + " means, algorithm requested " + k + " means instead.");
+ }
+ // Chose first mean
+ List<O> means = new ArrayList<>(k);
+
+ for(NumberVector v : initialMeans) {
+ means.add(factory.newNumberVector(v));
+ }
+ return means;
+ }
+
+ /**
+ * Parameterization class.
+ *
+ * @author Erich Schubert
+ *
+ * @apiviz.exclude
+ */
+ public static class Parameterizer extends AbstractParameterizer {
+ /**
+ * Option to specify the initial means to use.
+ */
+ public static final OptionID INITIAL_MEANS = new OptionID("kmeans.means", "Initial means for k-means.");
+
+ /**
+ * Initial means.
+ */
+ protected List<Vector> initialMeans;
+
+ @Override
+ protected void makeOptions(Parameterization config) {
+ super.makeOptions(config);
+ VectorListParameter meansP = new VectorListParameter(INITIAL_MEANS);
+ if(config.grab(meansP)) {
+ initialMeans = meansP.getValue();
+ }
+ }
+
+ @Override
+ protected PredefinedInitialMeans makeInstance() {
+ return new PredefinedInitialMeans(initialMeans);
+ }
+ }
+}