Import Upstream version 0.7.0

1 files changed, 96 insertions, 0 deletions

diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/math/geodesy/SphericalVincentyEarthModel.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/math/geodesy/SphericalVincentyEarthModel.java
new file mode 100644
index 00000000..7f627425
--- /dev/null
+++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/math/geodesy/SphericalVincentyEarthModel.java
@@ -0,0 +1,96 @@
+package de.lmu.ifi.dbs.elki.math.geodesy;
+
+/*
+ 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.math.MathUtil;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+
+/**
+ * A simple spherical earth model using radius 6371009 m.
+ * 
+ * @author Erich Schubert
+ */
+public class SphericalVincentyEarthModel extends AbstractEarthModel {
+  /**
+   * Spherical earth model, static instance.
+   */
+  public static final SphericalVincentyEarthModel STATIC = new SphericalVincentyEarthModel();
+
+  /**
+   * Earth radius approximation in m.
+   * 
+   * As per International Union of Geodesy and Geophysics (IUGG):
+   */
+  public static final double EARTH_RADIUS = 6371009; // m
+
+  /**
+   * Constructor.
+   */
+  protected SphericalVincentyEarthModel() {
+    super(EARTH_RADIUS, EARTH_RADIUS, 0., Double.POSITIVE_INFINITY);
+  }
+
+  @Override
+  public double[] latLngRadToECEF(double lat, double lng) {
+    // Then to sine and cosines:
+    final double clat = Math.cos(lat), slat = MathUtil.cosToSin(lat, clat);
+    final double clng = Math.cos(lng), slng = MathUtil.cosToSin(lng, clng);
+
+    return new double[] { EARTH_RADIUS * clat * clng, EARTH_RADIUS * clat * slng, EARTH_RADIUS * slat };
+  }
+
+  @Override
+  public double[] latLngRadToECEF(double lat, double lng, double h) {
+    // Then to sine and cosines:
+    final double clat = Math.cos(lat), slat = MathUtil.cosToSin(lat, clat);
+    final double clng = Math.cos(lng), slng = MathUtil.cosToSin(lng, clng);
+
+    return new double[] { (EARTH_RADIUS + h) * clat * clng, (EARTH_RADIUS + h) * clat * slng, (EARTH_RADIUS + h) * slat };
+  }
+
+  @Override
+  public double ecefToLatRad(double x, double y, double z) {
+    final double p = Math.sqrt(x * x + y * y);
+    return Math.atan2(z, p);
+  }
+
+  @Override
+  public double distanceRad(double lat1, double lng1, double lat2, double lng2) {
+    return EARTH_RADIUS * SphereUtil.sphericalVincentyFormulaRad(lat1, lng1, lat2, lng2);
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    @Override
+    protected SphericalVincentyEarthModel makeInstance() {
+      return STATIC;
+    }
+  }
+}