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authorAndrej Shadura <andrewsh@debian.org>2019-03-09 22:30:41 +0000
committerAndrej Shadura <andrewsh@debian.org>2019-03-09 22:30:41 +0000
commit38212b3127e90751fb39cda34250bc11be62b76c (patch)
treedc1397346030e9695bd763dddc93b3be527cd643 /elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/minkowski/LPNormDistanceFunction.java
parent337087b668d3a54f3afee3a9adb597a32e9f7e94 (diff)
Import Upstream version 0.7.0
Diffstat (limited to 'elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/minkowski/LPNormDistanceFunction.java')
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diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/minkowski/LPNormDistanceFunction.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/minkowski/LPNormDistanceFunction.java
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+++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/minkowski/LPNormDistanceFunction.java
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+package de.lmu.ifi.dbs.elki.distance.distancefunction.minkowski;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2015
+ 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 de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.data.spatial.SpatialComparable;
+import de.lmu.ifi.dbs.elki.data.type.SimpleTypeInformation;
+import de.lmu.ifi.dbs.elki.data.type.TypeUtil;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractSpatialNorm;
+import de.lmu.ifi.dbs.elki.utilities.Alias;
+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.constraints.CommonConstraints;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.DoubleParameter;
+
+/**
+ * LP-Norm for {@link NumberVector}s.
+ *
+ * @author Arthur Zimek
+ *
+ * @apiviz.landmark
+ */
+@Alias({ "lp", "minkowski", "p", "de.lmu.ifi.dbs.elki.distance.distancefunction.LPNormDistanceFunction" })
+public class LPNormDistanceFunction extends AbstractSpatialNorm {
+ /**
+ * p parameter and its inverse.
+ */
+ protected double p, invp;
+
+ /**
+ * Constructor, internal version.
+ *
+ * @param p Parameter p
+ */
+ public LPNormDistanceFunction(double p) {
+ super();
+ this.p = p;
+ this.invp = 1. / p;
+ }
+
+ /**
+ * Compute unscaled distance in a range of dimensions.
+ *
+ * @param v1 First object
+ * @param v2 Second object
+ * @param start First dimension
+ * @param end Exclusive last dimension
+ * @param agg Current aggregate value
+ * @return Aggregated values.
+ */
+ private final double preDistance(NumberVector v1, NumberVector v2, final int start, final int end, double agg) {
+ for(int d = start; d < end; d++) {
+ final double xd = v1.doubleValue(d), yd = v2.doubleValue(d);
+ final double delta = (xd >= yd) ? xd - yd : yd - xd;
+ agg += Math.pow(delta, p);
+ }
+ return agg;
+ }
+
+ /**
+ * Compute unscaled distance in a range of dimensions.
+ *
+ * @param v First vector
+ * @param mbr Second MBR
+ * @param start First dimension
+ * @param end Exclusive last dimension
+ * @param agg Current aggregate value
+ * @return Aggregated values.
+ */
+ private final double preDistanceVM(NumberVector v, SpatialComparable mbr, final int start, final int end, double agg) {
+ for(int d = start; d < end; d++) {
+ final double value = v.doubleValue(d), min = mbr.getMin(d);
+ double delta = min - value;
+ if(delta < 0.) {
+ delta = value - mbr.getMax(d);
+ }
+ if(delta > 0.) {
+ agg += Math.pow(delta, p);
+ }
+ }
+ return agg;
+ }
+
+ /**
+ * Compute unscaled distance in a range of dimensions.
+ *
+ * @param mbr1 First MBR
+ * @param mbr2 Second MBR
+ * @param start First dimension
+ * @param end Exclusive last dimension
+ * @param agg Current aggregate value
+ * @return Aggregated values.
+ */
+ private final double preDistanceMBR(SpatialComparable mbr1, SpatialComparable mbr2, final int start, final int end, double agg) {
+ for(int d = start; d < end; d++) {
+ double delta = mbr2.getMin(d) - mbr1.getMax(d);
+ if(delta < 0.) {
+ delta = mbr1.getMin(d) - mbr2.getMax(d);
+ }
+ if(delta > 0.) {
+ agg += Math.pow(delta, p);
+ }
+ }
+ return agg;
+ }
+
+ /**
+ * Compute unscaled norm in a range of dimensions.
+ *
+ * @param v Data object
+ * @param start First dimension
+ * @param end Exclusive last dimension
+ * @param agg Current aggregate value
+ * @return Aggregated values.
+ */
+ private final double preNorm(NumberVector v, final int start, final int end, double agg) {
+ for(int d = start; d < end; d++) {
+ final double xd = v.doubleValue(d);
+ final double delta = xd >= 0. ? xd : -xd;
+ agg += Math.pow(delta, p);
+ }
+ return agg;
+ }
+
+ /**
+ * Compute unscaled norm in a range of dimensions.
+ *
+ * @param mbr Data object
+ * @param start First dimension
+ * @param end Exclusive last dimension
+ * @param agg Current aggregate value
+ * @return Aggregated values.
+ */
+ private final double preNormMBR(SpatialComparable mbr, final int start, final int end, double agg) {
+ for(int d = start; d < end; d++) {
+ double delta = mbr.getMin(d);
+ if(delta < 0.) {
+ delta = -mbr.getMax(d);
+ }
+ if(delta > 0.) {
+ agg += Math.pow(delta, p);
+ }
+ }
+ return agg;
+ }
+
+ @Override
+ public double distance(NumberVector v1, NumberVector v2) {
+ final int dim1 = v1.getDimensionality(), dim2 = v2.getDimensionality();
+ final int mindim = (dim1 < dim2) ? dim1 : dim2;
+ double agg = preDistance(v1, v2, 0, mindim, 0.);
+ if(dim1 > mindim) {
+ agg = preNorm(v1, mindim, dim1, agg);
+ }
+ else if(dim2 > mindim) {
+ agg = preNorm(v2, mindim, dim2, agg);
+ }
+ return Math.pow(agg, invp);
+ }
+
+ @Override
+ public double norm(NumberVector v) {
+ return Math.pow(preNorm(v, 0, v.getDimensionality(), 0.), invp);
+ }
+
+ @Override
+ public double minDist(SpatialComparable mbr1, SpatialComparable mbr2) {
+ final int dim1 = mbr1.getDimensionality(), dim2 = mbr2.getDimensionality();
+ final int mindim = (dim1 < dim2) ? dim1 : dim2;
+
+ final NumberVector v1 = (mbr1 instanceof NumberVector) ? (NumberVector) mbr1 : null;
+ final NumberVector v2 = (mbr2 instanceof NumberVector) ? (NumberVector) mbr2 : null;
+
+ double agg = 0.;
+ if(v1 != null) {
+ if(v2 != null) {
+ agg = preDistance(v1, v2, 0, mindim, agg);
+ }
+ else {
+ agg = preDistanceVM(v1, mbr2, 0, mindim, agg);
+ }
+ }
+ else {
+ if(v2 != null) {
+ agg = preDistanceVM(v2, mbr1, 0, mindim, agg);
+ }
+ else {
+ agg = preDistanceMBR(mbr1, mbr2, 0, mindim, agg);
+ }
+ }
+ // first object has more dimensions.
+ if(dim1 > mindim) {
+ if(v1 != null) {
+ agg = preNorm(v1, mindim, dim1, agg);
+ }
+ else {
+ agg = preNormMBR(v1, mindim, dim1, agg);
+ }
+ }
+ // second object has more dimensions.
+ if(dim2 > mindim) {
+ if(v2 != null) {
+ agg = preNorm(v2, mindim, dim2, agg);
+ }
+ else {
+ agg = preNormMBR(mbr2, mindim, dim2, agg);
+ }
+ }
+ return Math.pow(agg, invp);
+ }
+
+ @Override
+ public boolean isMetric() {
+ return (p >= 1.);
+ }
+
+ @Override
+ public String toString() {
+ return "L_" + p + "Norm";
+ }
+
+ /**
+ * Get the functions p parameter.
+ *
+ * @return p
+ */
+ public double getP() {
+ return p;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if(obj == null) {
+ return false;
+ }
+ if(obj instanceof LPNormDistanceFunction) {
+ return this.p == ((LPNormDistanceFunction) obj).p;
+ }
+ return false;
+ }
+
+ @Override
+ public SimpleTypeInformation<? super NumberVector> getInputTypeRestriction() {
+ return TypeUtil.NUMBER_VECTOR_VARIABLE_LENGTH;
+ }
+
+ /**
+ * Parameterization class.
+ *
+ * @author Erich Schubert
+ *
+ * @apiviz.exclude
+ */
+ public static class Parameterizer extends AbstractParameterizer {
+ /**
+ * OptionID for the "p" parameter
+ */
+ public static final OptionID P_ID = new OptionID("lpnorm.p", "the degree of the L-P-Norm (positive number)");
+ /**
+ * The value of p.
+ */
+ protected double p;
+
+ @Override
+ protected void makeOptions(Parameterization config) {
+ super.makeOptions(config);
+ final DoubleParameter paramP = new DoubleParameter(P_ID);
+ paramP.addConstraint(CommonConstraints.GREATER_THAN_ZERO_DOUBLE);
+ if(config.grab(paramP)) {
+ p = paramP.getValue();
+ }
+ }
+
+ @Override
+ protected LPNormDistanceFunction makeInstance() {
+ if(p == 1.) {
+ return ManhattanDistanceFunction.STATIC;
+ }
+ if(p == 2.) {
+ return EuclideanDistanceFunction.STATIC;
+ }
+ if(p == Double.POSITIVE_INFINITY) {
+ return MaximumDistanceFunction.STATIC;
+ }
+ if(p == Math.round(p)) {
+ return new LPIntegerNormDistanceFunction((int) p);
+ }
+ return new LPNormDistanceFunction(p);
+ }
+ }
+}