/*
* Encog(tm) Core v3.3 - Java Version
* http://www.heatonresearch.com/encog/
* https://github.com/encog/encog-java-core
* Copyright 2008-2014 Heaton Research, Inc.
*
* Licensed 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.
*
* For more information on Heaton Research copyrights, licenses
* and trademarks visit:
* http://www.heatonresearch.com/copyright
*/
package org.encog.ml.graph;
import junit.framework.Assert;
import junit.framework.TestCase;
import org.encog.ml.graph.search.AStarSearch;
import org.encog.ml.graph.search.BreadthFirstSearch;
import org.encog.ml.graph.search.DepthFirstSearch;
import org.encog.ml.graph.search.EuclideanCostEstimator;
import org.encog.ml.graph.search.GraphSearch;
import org.encog.ml.graph.search.SimpleDestinationGoal;
public class TestSearch extends TestCase {
private int countIterations(GraphSearch search) {
int result = 0;
while( search.getSolution()==null ) {
search.iteration();
result++;
}
return result;
}
public void testDepthFirstSearch() {
BasicNode nodeA = new BasicNode("a");
BasicGraph graph = new BasicGraph(nodeA);
BasicNode nodeB = graph.connect(nodeA,new BasicNode("b"),5);
BasicNode nodeC = graph.connect(nodeA,new BasicNode("c"),2);
BasicNode nodeD = graph.connect(nodeB, new BasicNode("d"), 1);
nodeC.connect(nodeD, 1);
DepthFirstSearch search = new DepthFirstSearch(graph,nodeA,new SimpleDestinationGoal(nodeD));
Assert.assertEquals(3, countIterations(search));
BasicPath solution = search.getSolution();
Assert.assertEquals(solution.getNodes().get(0).getLabel(), "a");
Assert.assertEquals(solution.getNodes().get(1).getLabel(), "b");
Assert.assertEquals(solution.getNodes().get(2).getLabel(), "d");
}
public void testBredthFirstSearch() {
BasicNode nodeA = new BasicNode("a");
BasicGraph graph = new BasicGraph(nodeA);
BasicNode nodeB = graph.connect(nodeA,new BasicNode("b"),5);
BasicNode nodeC = graph.connect(nodeA,new BasicNode("c"),2);
BasicNode nodeD = graph.connect(nodeB, new BasicNode("d"), 1);
nodeC.connect(nodeD, 1);
BreadthFirstSearch search = new BreadthFirstSearch(graph,nodeA,new SimpleDestinationGoal(nodeD));
Assert.assertEquals(4, countIterations(search));
BasicPath solution = search.getSolution();
Assert.assertEquals(solution.getNodes().get(0).getLabel(), "a");
Assert.assertEquals(solution.getNodes().get(1).getLabel(), "b");
Assert.assertEquals(solution.getNodes().get(2).getLabel(), "d");
}
public void testAStar() {
EuclideanNode nodeA = new EuclideanNode("a", 0, 0);
BasicGraph graph = new BasicGraph(nodeA);
BasicNode nodeB = graph.connect(nodeA, new EuclideanNode("b",0,2), 10.0);
BasicNode nodeC = graph.connect(nodeA, new EuclideanNode("c",0,1), 1.0);
BasicNode nodeD = graph.connect(nodeB, new EuclideanNode("d",0,1), 1.0);
nodeD.connect(nodeD, 1.0);
nodeC.connect(nodeD, 1.0);
AStarSearch search = new AStarSearch(
graph,
nodeA,
new SimpleDestinationGoal(nodeD),
new EuclideanCostEstimator());
Assert.assertEquals(3, countIterations(search));
BasicPath solution = search.getSolution();
Assert.assertEquals(solution.getNodes().get(0).getLabel(), "a");
Assert.assertEquals(solution.getNodes().get(1).getLabel(), "c");
Assert.assertEquals(solution.getNodes().get(2).getLabel(), "d");
}
}