|
Java example source code file (ConvexHullGenerator2DAbstractTest.java)
This example Java source code file (ConvexHullGenerator2DAbstractTest.java) is included in the alvinalexander.com
"Java Source Code
Warehouse" project. The intent of this project is to help you "Learn
Java by Example" TM.
Learn more about this Java project at its project page.
The ConvexHullGenerator2DAbstractTest.java Java example source code
/*
* 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.hull;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import org.apache.commons.math3.exception.NullArgumentException;
import org.apache.commons.math3.geometry.euclidean.twod.Euclidean2D;
import org.apache.commons.math3.geometry.euclidean.twod.Vector2D;
import org.apache.commons.math3.geometry.partitioning.Region;
import org.apache.commons.math3.geometry.partitioning.Region.Location;
import org.apache.commons.math3.random.MersenneTwister;
import org.apache.commons.math3.random.RandomGenerator;
import org.apache.commons.math3.util.FastMath;
import org.apache.commons.math3.util.MathArrays;
import org.apache.commons.math3.util.Precision;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
/**
* Abstract base test class for 2D convex hull generators.
*
*/
public abstract class ConvexHullGenerator2DAbstractTest {
protected ConvexHullGenerator2D generator;
protected RandomGenerator random;
protected abstract ConvexHullGenerator2D createConvexHullGenerator(boolean includeCollinearPoints);
protected Collection<Vector2D> reducePoints(Collection points) {
// do nothing by default, may be overridden by other tests
return points;
}
@Before
public void setUp() {
// by default, do not include collinear points
generator = createConvexHullGenerator(false);
random = new MersenneTwister(10);
}
// ------------------------------------------------------------------------------
@Test(expected = NullArgumentException.class)
public void testNullArgument() {
generator.generate(null);
}
@Test
public void testEmpty() {
ConvexHull2D hull = generator.generate(Collections.<Vector2D>emptyList());
Assert.assertTrue(hull.getVertices().length == 0);
Assert.assertTrue(hull.getLineSegments().length == 0);
}
@Test
public void testOnePoint() {
List<Vector2D> points = createRandomPoints(1);
ConvexHull2D hull = generator.generate(points);
Assert.assertTrue(hull.getVertices().length == 1);
Assert.assertTrue(hull.getLineSegments().length == 0);
}
@Test
public void testTwoPoints() {
List<Vector2D> points = createRandomPoints(2);
ConvexHull2D hull = generator.generate(points);
Assert.assertTrue(hull.getVertices().length == 2);
Assert.assertTrue(hull.getLineSegments().length == 1);
}
@Test
public void testAllIdentical() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(1, 1));
points.add(new Vector2D(1, 1));
points.add(new Vector2D(1, 1));
final ConvexHull2D hull = generator.generate(points);
Assert.assertTrue(hull.getVertices().length == 1);
}
@Test
public void testConvexHull() {
// execute 100 random variations
for (int i = 0; i < 100; i++) {
// randomize the size from 4 to 100
int size = (int) FastMath.floor(random.nextDouble() * 96.0 + 4.0);
List<Vector2D> points = createRandomPoints(size);
ConvexHull2D hull = generator.generate(reducePoints(points));
checkConvexHull(points, hull);
}
}
@Test
public void testCollinearPoints() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(4, 1));
points.add(new Vector2D(10, 1));
final ConvexHull2D hull = generator.generate(points);
checkConvexHull(points, hull);
}
@Test
public void testCollinearPointsReverse() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(10, 1));
points.add(new Vector2D(4, 1));
final ConvexHull2D hull = generator.generate(points);
checkConvexHull(points, hull);
}
@Test
public void testCollinearPointsIncluded() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(4, 1));
points.add(new Vector2D(10, 1));
final ConvexHull2D hull = createConvexHullGenerator(true).generate(points);
checkConvexHull(points, hull, true);
}
@Test
public void testCollinearPointsIncludedReverse() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(10, 1));
points.add(new Vector2D(4, 1));
final ConvexHull2D hull = createConvexHullGenerator(true).generate(points);
checkConvexHull(points, hull, true);
}
@Test
public void testIdenticalPoints() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(4, 1));
points.add(new Vector2D(1, 1));
final ConvexHull2D hull = generator.generate(points);
checkConvexHull(points, hull);
}
@Test
public void testIdenticalPoints2() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(4, 1));
points.add(new Vector2D(1, 1));
final ConvexHull2D hull = createConvexHullGenerator(true).generate(points);
checkConvexHull(points, hull, true);
}
@Test
public void testClosePoints() {
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(1, 1));
points.add(new Vector2D(2, 2));
points.add(new Vector2D(2, 4));
points.add(new Vector2D(4, 1));
points.add(new Vector2D(1.00001, 1));
final ConvexHull2D hull = generator.generate(points);
checkConvexHull(points, hull);
}
@Test
public void testCollinearPointOnExistingBoundary() {
// MATH-1135: check that collinear points on the hull are handled correctly
// when only a minimal hull shall be constructed
final Collection<Vector2D> points = new ArrayList();
points.add(new Vector2D(7.3152, 34.7472));
points.add(new Vector2D(6.400799999999997, 34.747199999999985));
points.add(new Vector2D(5.486399999999997, 34.7472));
points.add(new Vector2D(4.876799999999999, 34.7472));
points.add(new Vector2D(4.876799999999999, 34.1376));
points.add(new Vector2D(4.876799999999999, 30.48));
points.add(new Vector2D(6.0959999999999965, 30.48));
points.add(new Vector2D(6.0959999999999965, 34.1376));
points.add(new Vector2D(7.315199999999996, 34.1376));
points.add(new Vector2D(7.3152, 30.48));
final ConvexHull2D hull = createConvexHullGenerator(false).generate(points);
checkConvexHull(points, hull);
}
@Test
public void testCollinearPointsInAnyOrder() {
// MATH-1148: collinear points on the hull might be in any order
// make sure that they are processed in the proper order
// for each algorithm.
List<Vector2D> points = new ArrayList();
// first case: 3 points are collinear
points.add(new Vector2D(16.078200000000184, -36.52519999989808));
points.add(new Vector2D(19.164300000000186, -36.52519999989808));
points.add(new Vector2D(19.1643, -25.28136477910407));
points.add(new Vector2D(19.1643, -17.678400000004157));
ConvexHull2D hull = createConvexHullGenerator(false).generate(points);
checkConvexHull(points, hull);
hull = createConvexHullGenerator(true).generate(points);
checkConvexHull(points, hull, true);
points.clear();
// second case: multiple points are collinear
points.add(new Vector2D(0, -29.959696875));
points.add(new Vector2D(0, -31.621809375));
points.add(new Vector2D(0, -28.435696875));
points.add(new Vector2D(0, -33.145809375));
points.add(new Vector2D(3.048, -33.145809375));
points.add(new Vector2D(3.048, -31.621809375));
points.add(new Vector2D(3.048, -29.959696875));
points.add(new Vector2D(4.572, -33.145809375));
points.add(new Vector2D(4.572, -28.435696875));
hull = createConvexHullGenerator(false).generate(points);
checkConvexHull(points, hull);
hull = createConvexHullGenerator(true).generate(points);
checkConvexHull(points, hull, true);
}
@Test
public void testIssue1123() {
List<Vector2D> points = new ArrayList();
int[][] data = new int[][] { { -11, -1 }, { -11, 0 }, { -11, 1 },
{ -10, -3 }, { -10, -2 }, { -10, -1 }, { -10, 0 }, { -10, 1 },
{ -10, 2 }, { -10, 3 }, { -9, -4 }, { -9, -3 }, { -9, -2 },
{ -9, -1 }, { -9, 0 }, { -9, 1 }, { -9, 2 }, { -9, 3 },
{ -9, 4 }, { -8, -5 }, { -8, -4 }, { -8, -3 }, { -8, -2 },
{ -8, -1 }, { -8, 0 }, { -8, 1 }, { -8, 2 }, { -8, 3 },
{ -8, 4 }, { -8, 5 }, { -7, -6 }, { -7, -5 }, { -7, -4 },
{ -7, -3 }, { -7, -2 }, { -7, -1 }, { -7, 0 }, { -7, 1 },
{ -7, 2 }, { -7, 3 }, { -7, 4 }, { -7, 5 }, { -7, 6 },
{ -6, -7 }, { -6, -6 }, { -6, -5 }, { -6, -4 }, { -6, -3 },
{ -6, -2 }, { -6, -1 }, { -6, 0 }, { -6, 1 }, { -6, 2 },
{ -6, 3 }, { -6, 4 }, { -6, 5 }, { -6, 6 }, { -6, 7 },
{ -5, -7 }, { -5, -6 }, { -5, -5 }, { -5, -4 }, { -5, -3 },
{ -5, -2 }, { -5, 4 }, { -5, 5 }, { -5, 6 }, { -5, 7 },
{ -4, -7 }, { -4, -6 }, { -4, -5 }, { -4, -4 }, { -4, -3 },
{ -4, -2 }, { -4, 4 }, { -4, 5 }, { -4, 6 }, { -4, 7 },
{ -3, -8 }, { -3, -7 }, { -3, -6 }, { -3, -5 }, { -3, -4 },
{ -3, -3 }, { -3, -2 }, { -3, 4 }, { -3, 5 }, { -3, 6 },
{ -3, 7 }, { -3, 8 }, { -2, -8 }, { -2, -7 }, { -2, -6 },
{ -2, -5 }, { -2, -4 }, { -2, -3 }, { -2, -2 }, { -2, 4 },
{ -2, 5 }, { -2, 6 }, { -2, 7 }, { -2, 8 }, { -1, -8 },
{ -1, -7 }, { -1, -6 }, { -1, -5 }, { -1, -4 }, { -1, -3 },
{ -1, -2 }, { -1, 4 }, { -1, 5 }, { -1, 6 }, { -1, 7 },
{ -1, 8 }, { 0, -8 }, { 0, -7 }, { 0, -6 }, { 0, -5 },
{ 0, -4 }, { 0, -3 }, { 0, -2 }, { 0, 4 }, { 0, 5 }, { 0, 6 },
{ 0, 7 }, { 0, 8 }, { 1, -8 }, { 1, -7 }, { 1, -6 }, { 1, -5 },
{ 1, -4 }, { 1, -3 }, { 1, -2 }, { 1, -1 }, { 1, 0 }, { 1, 1 },
{ 1, 2 }, { 1, 3 }, { 1, 4 }, { 1, 5 }, { 1, 6 }, { 1, 7 },
{ 1, 8 }, { 2, -8 }, { 2, -7 }, { 2, -6 }, { 2, -5 },
{ 2, -4 }, { 2, -3 }, { 2, -2 }, { 2, -1 }, { 2, 0 }, { 2, 1 },
{ 2, 2 }, { 2, 3 }, { 2, 4 }, { 2, 5 }, { 2, 6 }, { 2, 7 },
{ 2, 8 }, { 3, -8 }, { 3, -7 }, { 3, -6 }, { 3, -5 },
{ 3, -4 }, { 3, -3 }, { 3, -2 }, { 3, -1 }, { 3, 0 }, { 3, 1 },
{ 3, 2 }, { 3, 3 }, { 3, 4 }, { 3, 5 }, { 3, 6 }, { 3, 7 },
{ 3, 8 }, { 4, -7 }, { 4, -6 }, { 4, -5 }, { 4, -4 },
{ 4, -3 }, { 4, -2 }, { 4, -1 }, { 4, 0 }, { 4, 1 }, { 4, 2 },
{ 4, 3 }, { 4, 4 }, { 4, 5 }, { 4, 6 }, { 4, 7 }, { 5, -7 },
{ 5, -6 }, { 5, -5 }, { 5, -4 }, { 5, -3 }, { 5, -2 },
{ 5, -1 }, { 5, 0 }, { 5, 1 }, { 5, 2 }, { 5, 3 }, { 5, 4 },
{ 5, 5 }, { 5, 6 }, { 5, 7 }, { 6, -7 }, { 6, -6 }, { 6, -5 },
{ 6, -4 }, { 6, -3 }, { 6, -2 }, { 6, -1 }, { 6, 0 }, { 6, 1 },
{ 6, 2 }, { 6, 3 }, { 6, 4 }, { 6, 5 }, { 6, 6 }, { 6, 7 },
{ 7, -6 }, { 7, -5 }, { 7, -4 }, { 7, -3 }, { 7, -2 },
{ 7, -1 }, { 7, 0 }, { 7, 1 }, { 7, 2 }, { 7, 3 }, { 7, 4 },
{ 7, 5 }, { 7, 6 }, { 8, -5 }, { 8, -4 }, { 8, -3 }, { 8, -2 },
{ 8, -1 }, { 8, 0 }, { 8, 1 }, { 8, 2 }, { 8, 3 }, { 8, 4 },
{ 8, 5 }, { 9, -4 }, { 9, -3 }, { 9, -2 }, { 9, -1 }, { 9, 0 },
{ 9, 1 }, { 9, 2 }, { 9, 3 }, { 9, 4 }, { 10, -3 }, { 10, -2 },
{ 10, -1 }, { 10, 0 }, { 10, 1 }, { 10, 2 }, { 10, 3 },
{ 11, -1 }, { 11, 0 }, { 11, 1 } };
for (int[] line : data) {
points.add(new Vector2D(line[0], line[1]));
}
Vector2D[] referenceHull = new Vector2D[] {
new Vector2D(-11.0, -1.0),
new Vector2D(-10.0, -3.0),
new Vector2D( -6.0, -7.0),
new Vector2D( -3.0, -8.0),
new Vector2D( 3.0, -8.0),
new Vector2D( 6.0, -7.0),
new Vector2D( 10.0, -3.0),
new Vector2D( 11.0, -1.0),
new Vector2D( 11.0, 1.0),
new Vector2D( 10.0, 3.0),
new Vector2D( 6.0, 7.0),
new Vector2D( 3.0, 8.0),
new Vector2D( -3.0, 8.0),
new Vector2D( -6.0, 7.0),
new Vector2D(-10.0, 3.0),
new Vector2D(-11.0, 1.0),
};
ConvexHull2D convHull = generator.generate(points);
Region<Euclidean2D> hullRegion = convHull.createRegion();
Assert.assertEquals(274.0, hullRegion.getSize(), 1.0e-12);
double perimeter = 0;
for (int i = 0; i < referenceHull.length; ++i) {
perimeter += Vector2D.distance(referenceHull[i],
referenceHull[(i + 1) % referenceHull.length]);
}
Assert.assertEquals(perimeter, hullRegion.getBoundarySize(), 1.0e-12);
for (int i = 0; i < referenceHull.length; ++i) {
Assert.assertEquals(Location.BOUNDARY, hullRegion.checkPoint(referenceHull[i]));
}
}
// ------------------------------------------------------------------------------
protected final List<Vector2D> createRandomPoints(int size) {
// create the cloud container
List<Vector2D> points = new ArrayList(size);
// fill the cloud with a random distribution of points
for (int i = 0; i < size; i++) {
points.add(new Vector2D(random.nextDouble() * 2.0 - 1.0, random.nextDouble() * 2.0 - 1.0));
}
return points;
}
protected final void checkConvexHull(final Collection<Vector2D> points, final ConvexHull2D hull) {
checkConvexHull(points, hull, false);
}
protected final void checkConvexHull(final Collection<Vector2D> points, final ConvexHull2D hull,
final boolean includesCollinearPoints) {
checkConvexHull(points, hull, includesCollinearPoints, 1e-10);
}
protected final void checkConvexHull(final Collection<Vector2D> points, final ConvexHull2D hull,
final boolean includesCollinearPoints, final double tolerance) {
Assert.assertNotNull(hull);
Assert.assertTrue(isConvex(hull, includesCollinearPoints, tolerance));
checkPointsInsideHullRegion(points, hull, includesCollinearPoints);
}
// verify that the constructed hull is really convex
protected final boolean isConvex(final ConvexHull2D hull, final boolean includesCollinearPoints,
final double tolerance) {
final Vector2D[] points = hull.getVertices();
int sign = 0;
for (int i = 0; i < points.length; i++) {
Vector2D p1 = points[i == 0 ? points.length - 1 : i - 1];
Vector2D p2 = points[i];
Vector2D p3 = points[i == points.length - 1 ? 0 : i + 1];
Vector2D d1 = p2.subtract(p1);
Vector2D d2 = p3.subtract(p2);
Assert.assertTrue(d1.getNorm() > 1e-10);
Assert.assertTrue(d2.getNorm() > 1e-10);
final double cross = MathArrays.linearCombination(d1.getX(), d2.getY(), -d1.getY(), d2.getX());
final int cmp = Precision.compareTo(cross, 0.0, tolerance);
if (sign != 0 && cmp != sign) {
if (includesCollinearPoints && cmp == 0) {
// in case of collinear points the cross product will be zero
} else {
return false;
}
}
sign = cmp;
}
return true;
}
// verify that all points are inside the convex hull region
protected final void checkPointsInsideHullRegion(final Collection<Vector2D> points,
final ConvexHull2D hull,
final boolean includesCollinearPoints) {
final Collection<Vector2D> hullVertices = Arrays.asList(hull.getVertices());
final Region<Euclidean2D> region = hull.createRegion();
for (final Vector2D p : points) {
Location location = region.checkPoint(p);
Assert.assertTrue(location != Location.OUTSIDE);
if (location == Location.BOUNDARY && includesCollinearPoints) {
Assert.assertTrue(hullVertices.contains(p));
}
}
}
}
Other Java examples (source code examples)
Here is a short list of links related to this Java ConvexHullGenerator2DAbstractTest.java source code file:
|