Merge pull request #69 from TheTransitClock/tc_issue_68

Use Kalman to predict partial stop paths.

transitclock/src/main/java/org/transitclock/core/predictiongenerator/kalman/KalmanPredictionGeneratorImpl.java

@@ -10,10 +10,12 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.transitclock.applications.Core;
+import org.transitclock.config.BooleanConfigValue;
 import org.transitclock.config.DoubleConfigValue;
 import org.transitclock.config.IntegerConfigValue;
 import org.transitclock.core.Indices;
 import org.transitclock.core.PredictionGeneratorDefaultImpl;
+import org.transitclock.core.SpatialMatch;
 import org.transitclock.core.TravelTimeDetails;
 import org.transitclock.core.VehicleState;
 import org.transitclock.core.dataCache.ArrivalDepartureComparator;
@@ -44,11 +46,11 @@ public class KalmanPredictionGeneratorImpl extends PredictionGeneratorDefaultImp
 	 * historical value. 
 	 */
 	private static final IntegerConfigValue minKalmanDays = new IntegerConfigValue(
-			"transitclock.prediction.data.kalman.mindays", new Integer(3),
+			"transitclock.prediction.data.kalman.mindays", new Integer(2),
 			"Min number of days trip data that needs to be available before Kalman prediciton is used instead of default transiTime prediction.");
 
 	private static final IntegerConfigValue maxKalmanDays = new IntegerConfigValue(
-			"transitclock.prediction.data.kalman.maxdays", new Integer(3),
+			"transitclock.prediction.data.kalman.maxdays", new Integer(2),
 			"Max number of historical days trips to include in Kalman prediction calculation.");
 
 	private static final IntegerConfigValue maxKalmanDaysToSearch = new IntegerConfigValue(
@@ -58,6 +60,13 @@ public class KalmanPredictionGeneratorImpl extends PredictionGeneratorDefaultImp
 	private static final DoubleConfigValue initialErrorValue = new DoubleConfigValue(
 			"transitclock.prediction.data.kalman.initialerrorvalue", new Double(100),
 			"Initial Kalman error value to use to start filter.");
+
+	/* May be better to use the default implementation as it splits things down into segments. */
+	private static final BooleanConfigValue useKalmanForPartialStopPaths = new BooleanConfigValue (
+			"transitclock.prediction.data.kalman.usekalmanforpartialstoppaths", new Boolean(true), 
+			"Will use Kalman prediction to get to first stop of prediction."
+	);
+
 
 	private static final Logger logger = LoggerFactory.getLogger(KalmanPredictionGeneratorImpl.class);
 
@@ -171,6 +180,33 @@ public long getTravelTimeForPath(Indices indices, AvlReport avlReport, VehicleSt
 		return super.getTravelTimeForPath(indices, avlReport, vehicleState);
 	}
 
+	@Override
+	public long expectedTravelTimeFromMatchToEndOfStopPath(AvlReport avlReport, SpatialMatch match) {
+
+		if(useKalmanForPartialStopPaths.getValue().booleanValue())
+		{		
+			VehicleStateManager vehicleStateManager = VehicleStateManager.getInstance();
+
+			VehicleState currentVehicleState = vehicleStateManager.getVehicleState(avlReport.getVehicleId());	
+
+			long fulltime = this.getTravelTimeForPath(match.getIndices(), avlReport, currentVehicleState);
+
+			double distanceAlongStopPath = match.getDistanceAlongStopPath();
+
+			double stopPathLength =
+					match.getStopPath().getLength();
+
+			long remainingtime = (long) (fulltime * ((stopPathLength-distanceAlongStopPath)/stopPathLength));
+
+			logger.debug("Using Kalman for first stop path {} with value {} instead of {}.", match.getIndices(), remainingtime, super.expectedTravelTimeFromMatchToEndOfStopPath(avlReport, match));
+
+			return remainingtime;
+		}else
+		{
+			return super.expectedTravelTimeFromMatchToEndOfStopPath(avlReport, match);
+		}
+	}
+
 	private Double lastVehiclePredictionError(KalmanErrorCache cache, Indices indices) {		
 		Double result = cache.getErrorValue(indices);
 		if(result!=null)