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authorErich Schubert <erich@debian.org>2012-06-02 17:47:03 +0200
committerAndrej Shadura <andrewsh@debian.org>2019-03-09 22:30:32 +0000
commit593eae6c91717eb9f4ff5088ba460dd4210509c0 (patch)
treed97e8cefb48773a382542e9e9d4a6796202a044a /src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/SubspaceEuclideanDistanceFunction.java
parente580e42664ca92fbf8792bc39b8d59383db829fe (diff)
parentc36aa2a8fd31ca5e225ff30278e910070cd2c8c1 (diff)
Import Debian changes 0.5.0~beta2-1
elki (0.5.0~beta2-1) unstable; urgency=low * New upstream beta release. * Needs GNU Trove 3, in NEW. * Build with OpenJDK7, as OpenJDK6 complains. elki (0.5.0~beta1-1) unstable; urgency=low * New upstream beta release. * Needs GNU Trove 3, not yet in Debian (private package) * Build with OpenJDK7, as OpenJDK6 complains.
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diff --git a/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/SubspaceEuclideanDistanceFunction.java b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/SubspaceEuclideanDistanceFunction.java
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+package de.lmu.ifi.dbs.elki.distance.distancefunction.subspace;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2012
+ 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.BitSet;
+
+import de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.data.spatial.SpatialComparable;
+
+/**
+ * Provides a distance function that computes the Euclidean distance between
+ * feature vectors only in specified dimensions.
+ *
+ * @author Elke Achtert
+ */
+public class SubspaceEuclideanDistanceFunction extends SubspaceLPNormDistanceFunction {
+ /**
+ * Constructor.
+ *
+ * @param dimensions Selected dimensions
+ */
+ public SubspaceEuclideanDistanceFunction(BitSet dimensions) {
+ super(2.0, dimensions);
+ }
+
+ /**
+ * Provides the Euclidean distance between two given feature vectors in the
+ * selected dimensions.
+ *
+ * @param v1 first feature vector
+ * @param v2 second feature vector
+ * @return the Euclidean distance between two given feature vectors in the
+ * selected dimensions
+ */
+ @Override
+ public double doubleDistance(NumberVector<?, ?> v1, NumberVector<?, ?> v2) {
+ if(v1.getDimensionality() != v2.getDimensionality()) {
+ throw new IllegalArgumentException("Different dimensionality of FeatureVectors\n " + "first argument: " + v1 + "\n " + "second argument: " + v2);
+ }
+
+ double sqrDist = 0;
+ for(int d = dimensions.nextSetBit(0); d >= 0; d = dimensions.nextSetBit(d + 1)) {
+ final double delta = v1.doubleValue(d + 1) - v2.doubleValue(d + 1);
+ sqrDist += delta * delta;
+ }
+ return Math.sqrt(sqrDist);
+ }
+
+ @Override
+ protected double doubleMinDistObject(SpatialComparable mbr, NumberVector<?, ?> v) {
+ if(mbr.getDimensionality() != v.getDimensionality()) {
+ throw new IllegalArgumentException("Different dimensionality of objects\n " + "first argument: " + mbr.toString() + "\n " + "second argument: " + v.toString());
+ }
+
+ double sqrDist = 0;
+ for(int d = dimensions.nextSetBit(0); d >= 0; d = dimensions.nextSetBit(d + 1)) {
+ final double delta;
+ final double value = v.doubleValue(d + 1);
+ final double omin = mbr.getMin(d + 1);
+ if(value < omin) {
+ delta = omin - value;
+ }
+ else {
+ final double omax = mbr.getMax(d + 1);
+ if(value > omax) {
+ delta = value - omax;
+ }
+ else {
+ continue;
+ }
+ }
+ sqrDist += delta * delta;
+ }
+ return Math.sqrt(sqrDist);
+ }
+
+ @Override
+ public double doubleMinDist(SpatialComparable mbr1, SpatialComparable mbr2) {
+ if(mbr1.getDimensionality() != mbr2.getDimensionality()) {
+ throw new IllegalArgumentException("Different dimensionality of objects\n " + "first argument: " + mbr1.toString() + "\n " + "second argument: " + mbr2.toString());
+ }
+ double sqrDist = 0;
+ for(int d = dimensions.nextSetBit(0); d >= 0; d = dimensions.nextSetBit(d + 1)) {
+ final double delta;
+ final double max1 = mbr1.getMax(d + 1);
+ final double min2 = mbr2.getMin(d + 1);
+ if(max1 < min2) {
+ delta = min2 - max1;
+ }
+ else {
+ final double min1 = mbr1.getMin(d + 1);
+ final double max2 = mbr2.getMax(d + 1);
+ if(min1 > max2) {
+ delta = min1 - max2;
+ }
+ else { // The mbrs intersect!
+ continue;
+ }
+ }
+ sqrDist += delta * delta;
+ }
+ return Math.sqrt(sqrDist);
+ }
+
+ @Override
+ public double doubleNorm(NumberVector<?, ?> obj) {
+ double sqrDist = 0;
+ for(int d = dimensions.nextSetBit(0); d >= 0; d = dimensions.nextSetBit(d + 1)) {
+ final double delta = obj.doubleValue(d + 1);
+ sqrDist += delta * delta;
+ }
+ return Math.sqrt(sqrDist);
+ }
+
+ /**
+ * Parameterization class.
+ *
+ * @author Erich Schubert
+ *
+ * @apiviz.exclude
+ */
+ public static class Parameterizer extends AbstractDimensionsSelectingDoubleDistanceFunction.Parameterizer {
+ @Override
+ protected SubspaceEuclideanDistanceFunction makeInstance() {
+ return new SubspaceEuclideanDistanceFunction(dimensions);
+ }
+ }
+} \ No newline at end of file