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Posted to commits@commons.apache.org by lu...@apache.org on 2012/09/30 15:22:29 UTC
svn commit: r1392022 - in /commons/proper/math/trunk: ./ src/changes/
src/main/java/org/apache/commons/math3/geometry/euclidean/twod/
src/test/java/org/apache/commons/math3/geometry/euclidean/twod/
Author: luc
Date: Sun Sep 30 13:22:28 2012
New Revision: 1392022
URL: http://svn.apache.org/viewvc?rev=1392022&view=rev
Log:
Added distance to point to 2D Line and Segment.
Patch provided by Curtis Jensen applied with minor modifications.
JIRA: MATH-641
Added:
commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java (with props)
Modified:
commons/proper/math/trunk/pom.xml
commons/proper/math/trunk/src/changes/changes.xml
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Line.java
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Segment.java
commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/LineTest.java
Modified: commons/proper/math/trunk/pom.xml
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/pom.xml?rev=1392022&r1=1392021&r2=1392022&view=diff
==============================================================================
--- commons/proper/math/trunk/pom.xml (original)
+++ commons/proper/math/trunk/pom.xml Sun Sep 30 13:22:28 2012
@@ -193,6 +193,9 @@
<name>Matthias Hummel</name>
</contributor>
<contributor>
+ <name>Curtis Jensen</name>
+ </contributor>
+ <contributor>
<name>Ismael Juma</name>
</contributor>
<contributor>
Modified: commons/proper/math/trunk/src/changes/changes.xml
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/changes/changes.xml?rev=1392022&r1=1392021&r2=1392022&view=diff
==============================================================================
--- commons/proper/math/trunk/src/changes/changes.xml (original)
+++ commons/proper/math/trunk/src/changes/changes.xml Sun Sep 30 13:22:28 2012
@@ -52,8 +52,11 @@ If the output is not quite correct, chec
<body>
<release version="3.1" date="TBD" description="
">
+ <action dev="luc" type="fix" issue="MATH-641" due-to="Curtis Jensen">
+ Added distance to point to 2D Line and Segment.
+ </action>
<action dev="erans" type="fix" issue="MATH-783">
- "PowellOptimizer" (package "o.a.c.m.optimization.direct") uses
+ "PowellOptimizer" (package "o.a.c.m.optimization.direct") uses
"BrentOptimizer" as its internal line search optimizer. The fix
forces the convergence criterion of "BrentOptimizer" to use
function values (instead of domain values).
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Line.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Line.java?rev=1392022&r1=1392021&r2=1392022&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Line.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Line.java Sun Sep 30 13:22:28 2012
@@ -263,6 +263,18 @@ public class Line implements Hyperplane<
return FastMath.abs(getOffset(p)) < 1.0e-10;
}
+ /** Compute the distance between the instance and a point.
+ * This is a shortcut for invoking FastMath.abs(getOffset(p)),
+ * and provides consistency with what is in the
+ * org.apache.commons.math3.geometry.euclidean.threed.Line class.
+ *
+ * @param p to check
+ * @return distance between the instance and the point
+ */
+ public double distance(final Vector2D p) {
+ return FastMath.abs(getOffset(p));
+ }
+
/** Check the instance is parallel to another line.
* @param line other line to check
* @return true if the instance is parallel to the other line
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Segment.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Segment.java?rev=1392022&r1=1392021&r2=1392022&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Segment.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/Segment.java Sun Sep 30 13:22:28 2012
@@ -16,6 +16,7 @@
*/
package org.apache.commons.math3.geometry.euclidean.twod;
+import org.apache.commons.math3.util.FastMath;
/** Simple container for a two-points segment.
* @version $Id$
@@ -64,4 +65,43 @@ public class Segment {
return line;
}
+ /**
+ * Calculates the shortest distance from a point to this line segment.
+ * <p>
+ * If the perpendicular extension from the point to the line does not
+ * cross in the bounds of the line segment, the shortest distance to
+ * the two end points will be returned.
+ * </p>
+ *
+ * Algorithm adapted from: http://www.codeguru.com/forum/printthread.php?s=cc8cf0596231f9a7dba4da6e77c29db3&t=194400&pp=15&page=1
+ */
+ public double distance(final Vector2D p) {
+ final double deltaX = end.getX() - start.getX();
+ final double deltaY = end.getY() - start.getY();
+
+ final double r = ((p.getX() - start.getX()) * deltaX + (p.getY() - start.getY()) * deltaY) /
+ (deltaX * deltaX + deltaY * deltaY);
+
+ // r == 0 => P = startPt
+ // r == 1 => P = endPt
+ // r < 0 => P is on the backward extension of the segment
+ // r > 1 => P is on the forward extension of the segment
+ // 0 < r < 1 => P is on the segment
+
+ // if point isn't on the line segment, just return the shortest distance to the end points
+ if (r < 0 || r > 1) {
+ final double dist1 = getStart().distance(p);
+ final double dist2 = getEnd().distance(p);
+
+ return FastMath.min(dist1, dist2);
+ }
+ else {
+ // find point on line and see if it is in the line segment
+ final double px = start.getX() + r * deltaX;
+ final double py = start.getY() + r * deltaY;
+
+ final Vector2D interPt = new Vector2D(px, py);
+ return interPt.distance(p);
+ }
+ }
}
Modified: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/LineTest.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/LineTest.java?rev=1392022&r1=1392021&r2=1392022&view=diff
==============================================================================
--- commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/LineTest.java (original)
+++ commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/LineTest.java Sun Sep 30 13:22:28 2012
@@ -64,6 +64,13 @@ public class LineTest {
}
@Test
+ public void testDistance() {
+ Line l = new Line(new Vector2D(2, 1), new Vector2D(-2, -2));
+ Assert.assertEquals(+5.0, l.distance(new Vector2D(5, -3)), 1.0e-10);
+ Assert.assertEquals(+5.0, l.distance(new Vector2D(-5, 2)), 1.0e-10);
+ }
+
+ @Test
public void testPointAt() {
Line l = new Line(new Vector2D(2, 1), new Vector2D(-2, -2));
for (double a = -2.0; a < 2.0; a += 0.2) {
Added: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java?rev=1392022&view=auto
==============================================================================
--- commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java (added)
+++ commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java Sun Sep 30 13:22:28 2012
@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.math3.geometry.euclidean.twod;
+
+import org.apache.commons.math3.geometry.euclidean.twod.Line;
+import org.apache.commons.math3.geometry.euclidean.twod.Vector2D;
+import org.apache.commons.math3.util.FastMath;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SegmentTest {
+
+ @Test
+ public void testDistance() {
+ Vector2D start = new Vector2D(2, 2);
+ Vector2D end = new Vector2D(-2, -2);
+ Segment segment = new Segment(start, end, new Line(start, end));
+
+ // distance to center of segment
+ Assert.assertEquals(FastMath.sqrt(2), segment.distance(new Vector2D(1, -1)), 1.0e-10);
+
+ // distance a point on segment
+ Assert.assertEquals(FastMath.sin(Math.PI / 4.0), segment.distance(new Vector2D(0, -1)), 1.0e-10);
+
+ // distance to end point
+ Assert.assertEquals(FastMath.sqrt(8), segment.distance(new Vector2D(0, 4)), 1.0e-10);
+
+ // distance to start point
+ Assert.assertEquals(FastMath.sqrt(8), segment.distance(new Vector2D(0, -4)), 1.0e-10);
+ }
+}
Propchange: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java
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Propchange: commons/proper/math/trunk/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/SegmentTest.java
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svn:keywords = "Author Date Id Revision"