1 files changed, 88 insertions, 0 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/distance/distancefunction/geo/LatLngDistanceFunction.java b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/geo/LatLngDistanceFunction.java
new file mode 100644
index 00000000..0e0b27a0
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+++ b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/geo/LatLngDistanceFunction.java
@@ -0,0 +1,88 @@
+package de.lmu.ifi.dbs.elki.distance.distancefunction.geo;
+/*
+This file is part of ELKI:
+Environment for Developing KDD-Applications Supported by Index-Structures
+
+Copyright (C) 2011
+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.type.SimpleTypeInformation;
+import de.lmu.ifi.dbs.elki.data.type.VectorFieldTypeInformation;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractVectorDoubleDistanceFunction;
+import de.lmu.ifi.dbs.elki.math.MathUtil;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+
+/**
+ * Distance function for 2D vectors in Latitude, Longitude form.
+ * 
+ * @author Erich Schubert
+ */
+public class LatLngDistanceFunction extends AbstractVectorDoubleDistanceFunction {
+  /**
+   * Static instance
+   */
+  public static final LatLngDistanceFunction STATIC = new LatLngDistanceFunction();
+
+  /**
+   * Constructor. Use static instance instead!
+   */
+  @Deprecated
+  public LatLngDistanceFunction() {
+    super();
+  }
+
+  @Override
+  public double doubleDistance(NumberVector<?, ?> o1, NumberVector<?, ?> o2) {
+    return MathUtil.latlngDistance(o1.doubleValue(1), o1.doubleValue(2), o2.doubleValue(1), o2.doubleValue(2));
+  }
+
+  @Override
+  public SimpleTypeInformation<? super NumberVector<?, ?>> getInputTypeRestriction() {
+    return VectorFieldTypeInformation.get(NumberVector.class, 2);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if(obj == null) {
+      return false;
+    }
+    if(obj == this) {
+      return true;
+    }
+    if(this.getClass().equals(obj.getClass())) {
+      return true;
+    }
+    return super.equals(obj);
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    @Override
+    protected LatLngDistanceFunction makeInstance() {
+      return LatLngDistanceFunction.STATIC;
+    }
+  }
+}
+\ No newline at end of file