cs8803p4/test/aima/core/probability/mdp/ValueIterationTest2.java

package aima.core.probability.mdp;

import java.util.Map;

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import aima.core.environment.gridworld.GridCell;
import aima.core.environment.gridworld.GridWorld;
import aima.core.environment.gridworld.GridWorldAction;
import aima.core.environment.gridworld.GridWorldFactory;
import aima.core.probability.example.MDPFactory;
import aima.core.probability.mdp.MarkovDecisionProcess;
import aima.core.probability.mdp.search.ValueIteration;

/**
 * 
 * @author Woody
 *
 */
public class ValueIterationTest2 {
	public static final double DELTA_THRESHOLD = 1e-3;

	private GridWorld<Double> gw = null;
	private MarkovDecisionProcess<GridCell<Double>, GridWorldAction> mdp = null;
	private ValueIteration<GridCell<Double>, GridWorldAction> vi = null;

	final int maxTiles = 6;
	final int maxScore = 10;

	@Before
	public void setUp() {
		// take 10 turns to place 6 tiles
		double defaultPenalty = -0.04;

		gw = GridWorldFactory.createGridWorldForTileGame(maxTiles, maxScore,
				defaultPenalty);
		mdp = MDPFactory.createMDPForTileGame(gw, maxTiles, maxScore);

		// gamma = 1.0
		vi = new ValueIteration<GridCell<Double>, GridWorldAction>(0.9);
	}

	@Test
	public void testValueIterationForTileGame() {
		Map<GridCell<Double>, Double> U = vi.valueIteration(mdp, 1.0);

		for (int j = maxScore; j >= 1; j--) {
			StringBuilder sb = new StringBuilder();
			for (int i = 1; i <= maxTiles; i++) {
				sb.append(U.get(gw.getCellAt(i, j)));
				sb.append(" ");
			}
			System.out.println(sb.toString());
		}

		Assert.assertEquals(-0.1874236, U.get(gw.getCellAt(1, 1)), DELTA_THRESHOLD);
	}
}