Clean up classes in the stats package

- TripStatisticsBuilder
- TripStatistics
- ExtremityMonitor
- DoubleBuffer

MyTracks/src/com/google/android/apps/mytracks/io/file/GpxImporter.java

@@ -306,7 +306,7 @@ public class GpxImporter extends DefaultHandler {
       tripStatisticsBuilder = new TripStatisticsBuilder(0);
       tripStatisticsBuilder.pauseAt(0);
     }
-    track.setTripStatistics(tripStatisticsBuilder.getStatistics());
+    track.setTripStatistics(tripStatisticsBuilder.getTripStatistics());
     track.setNumberOfPoints(numberOfLocations);
     myTracksProviderUtils.updateTrack(track);
     tracksIds.add(track.getId());

MyTracks/src/com/google/android/apps/mytracks/io/fusiontables/SendFusionTablesAsyncTask.java

@@ -253,7 +253,7 @@ public class SendFusionTablesAsyncTask extends AbstractSendAsyncTask {
           elevationBuffer.setNext(metricUnits ? location.getAltitude()
               : location.getAltitude() * UnitConversions.M_TO_FT);
           if (i % elevationSamplingFrequency == 0) {
-            distances.add(tripStatisticsBuilder.getStatistics().getTotalDistance());
+            distances.add(tripStatisticsBuilder.getTripStatistics().getTotalDistance());
             elevations.add(elevationBuffer.getAverage());
           }
           lastLocation = location;
@@ -279,7 +279,7 @@ public class SendFusionTablesAsyncTask extends AbstractSendAsyncTask {
 
       // Create an end marker
       if (lastLocation != null) {
-        distances.add(tripStatisticsBuilder.getStatistics().getTotalDistance());
+        distances.add(tripStatisticsBuilder.getTripStatistics().getTotalDistance());
         elevations.add(elevationBuffer.getAverage());
         DescriptionGenerator descriptionGenerator = new DescriptionGeneratorImpl(context);
         track.setDescription(

MyTracks/src/com/google/android/apps/mytracks/io/maps/SendMapsAsyncTask.java

@@ -297,7 +297,7 @@ public class SendMapsAsyncTask extends AbstractSendAsyncTask {
           elevationBuffer.setNext(metricUnits ? location.getAltitude()
               : location.getAltitude() * UnitConversions.M_TO_FT);
           if (i % elevationSamplingFrequency == 0) {
-            distances.add(tripStatisticsBuilder.getStatistics().getTotalDistance());
+            distances.add(tripStatisticsBuilder.getTripStatistics().getTotalDistance());
             elevations.add(elevationBuffer.getAverage());
           }
           lastLocation = location;
@@ -323,7 +323,7 @@ public class SendMapsAsyncTask extends AbstractSendAsyncTask {
 
       // Create an end marker
       if (lastLocation != null) {
-        distances.add(tripStatisticsBuilder.getStatistics().getTotalDistance());
+        distances.add(tripStatisticsBuilder.getTripStatistics().getTotalDistance());
         elevations.add(elevationBuffer.getAverage());
         
         track.setDescription(getTrackDescription(track, distances, elevations));

MyTracks/src/com/google/android/apps/mytracks/services/TrackRecordingService.java

@@ -654,7 +654,7 @@ public class TrackRecordingService extends Service {
             }
           } while (cursor.moveToPrevious());
         }
-        statsBuilder.getStatistics().setMovingTime(stats.getMovingTime());
+        statsBuilder.getTripStatistics().setMovingTime(stats.getMovingTime());
         statsBuilder.pauseAt(stats.getStopTime());
         statsBuilder.resumeAt(System.currentTimeMillis());
       } else {
@@ -834,7 +834,7 @@ public class TrackRecordingService extends Service {
 
       // Update the current track:
       if (lastRecordedLocation != null && lastRecordedLocation.getLatitude() < 90) {
-        TripStatistics tripStatistics = statsBuilder.getStatistics();
+        TripStatistics tripStatistics = statsBuilder.getTripStatistics();
         tripStatistics.setStopTime(System.currentTimeMillis());
         
         if (recordingTrack.getStartId() < 0) {
@@ -865,8 +865,8 @@ public class TrackRecordingService extends Service {
       if (waypoint != null) {
         waypoint.setLength(length);
         waypoint.setDuration(
-            System.currentTimeMillis() - statsBuilder.getStatistics().getStartTime());
+            System.currentTimeMillis() - statsBuilder.getTripStatistics().getStartTime());
-        waypoint.setTripStatistics(waypointStatsBuilder.getStatistics());
+        waypoint.setTripStatistics(waypointStatsBuilder.getTripStatistics());
         providerUtils.updateWaypoint(waypoint);
       }
     }
@@ -896,7 +896,7 @@ public class TrackRecordingService extends Service {
     }
     waypoint.setTrackId(recordingTrackId);
     waypoint.setLength(length);
-    if (lastLocation == null || statsBuilder == null || statsBuilder.getStatistics() == null) {
+    if (lastLocation == null || statsBuilder == null || statsBuilder.getTripStatistics() == null) {
       if (!request.isTrackStatistics()) {
         return -1L;
       }
@@ -910,7 +910,7 @@ public class TrackRecordingService extends Service {
       waypoint.setLocation(location);
     } else {
       waypoint.setLocation(lastLocation);
-      waypoint.setDuration(lastLocation.getTime() - statsBuilder.getStatistics().getStartTime());
+      waypoint.setDuration(lastLocation.getTime() - statsBuilder.getTripStatistics().getStartTime());
     }
     Uri uri = providerUtils.insertWaypoint(waypoint);
     return Long.parseLong(uri.getLastPathSegment());
@@ -958,7 +958,7 @@ public class TrackRecordingService extends Service {
 
     // Override the duration - it's not the duration from the last waypoint, but
     // the duration from the beginning of the whole track
-    waypoint.setDuration(time - statsBuilder.getStatistics().getStartTime());
+    waypoint.setDuration(time - statsBuilder.getTripStatistics().getStartTime());
 
     // Set the rest of the waypoint data
     waypoint.setType(Waypoint.TYPE_STATISTICS);
@@ -973,7 +973,7 @@ public class TrackRecordingService extends Service {
       name = getString(R.string.marker_split_name_format, nextMarkerNumber);
     }
     waypoint.setName(name);
-    waypoint.setTripStatistics(waypointStatsBuilder.getStatistics());
+    waypoint.setTripStatistics(waypointStatsBuilder.getTripStatistics());
     waypoint.setDescription(descriptionGenerator.generateWaypointDescription(waypoint));
     waypoint.setIcon(getString(R.string.marker_statistics_icon_url));
 
@@ -1050,7 +1050,7 @@ public class TrackRecordingService extends Service {
   }
 
   public TripStatistics getTripStatistics() {
-    return statsBuilder.getStatistics();
+    return statsBuilder.getTripStatistics();
   }
 
   Location getLastLocation() {

MyTracks/src/com/google/android/apps/mytracks/stats/DoubleBuffer.java

@@ -25,61 +25,30 @@ package com.google.android.apps.mytracks.stats;
  */
 public class DoubleBuffer {
 
-  /**
+  // The location that the next write will occur at.
-   * The location that the next write will occur at.
-   */
   private int index;
 
-  /**
+  // The sliding buffer of doubles.
-   * The sliding buffer of doubles.
-   */
   private final double[] buffer;
 
-  /**
+  // True if the buffer is full
-   * Have all of the slots in the buffer been filled?
-   */
   private boolean isFull;
 
   /**
-   * Creates a buffer with size elements.
+   * Creates a buffer with a certain size.
    * 
-   * @param size the number of elements in the buffer
+   * @param size the size
-   * @throws IllegalArgumentException if the size is not a positive value
    */
   public DoubleBuffer(int size) {
     if (size < 1) {
-      throw new IllegalArgumentException("The buffer size must be positive.");
+      throw new IllegalArgumentException("The buffer size must be greater than 1.");
     }
     buffer = new double[size];
     reset();
   }
 
   /**
-   * Adds a double to the buffer. If the buffer is full the oldest element is
+   * Resets the buffer.
-   * overwritten.
-   *
-   * @param d the double to add
-   */
-  public void setNext(double d) {
-    if (index == buffer.length) {
-      index = 0;
-    }
-    buffer[index] = d;
-    index++;
-    if (index == buffer.length) {
-      isFull = true;
-    }
-  }
-
-  /**
-   * Are all of the entries in the buffer used?
-   */
-  public boolean isFull() {
-    return isFull;
-  }
-
-  /**
-   * Resets the buffer to the initial state.
    */
   public void reset() {
     index = 0;
@@ -87,16 +56,20 @@ public class DoubleBuffer {
   }
 
   /**
-   * Gets the average of values from the buffer.
+   * Returns true if the buffer is full.
-   *
+   */
-   * @return The average of the buffer
+  public boolean isFull() {
+    return isFull;
+  }
+
+  /**
+   * Gets the average of the buffer.
    */
   public double getAverage() {
     int numberOfEntries = isFull ? buffer.length : index;
     if (numberOfEntries == 0) {
       return 0;
     }
-
     double sum = 0;
     for (int i = 0; i < numberOfEntries; i++) {
       sum += buffer[i];
@@ -105,15 +78,15 @@ public class DoubleBuffer {
   }
 
   /**
-   * Gets the average and standard deviation of the buffer.
+   * Gets the average and the variance of the buffer.
    * 
-   * @return An array of two elements - the first is the average, and the second
+   * @return an array of two elements - the first is the average, the second is
-   *         is the variance
+   *         the variance
    */
   public double[] getAverageAndVariance() {
     int numberOfEntries = isFull ? buffer.length : index;
     if (numberOfEntries == 0) {
-      return new double[]{0, 0};
+      return new double[] { 0, 0 };
     }
 
     double sum = 0;
@@ -124,8 +97,25 @@ public class DoubleBuffer {
     }
 
     double average = sum / numberOfEntries;
-    return new double[]{average,
+    double variance = sumSquares / numberOfEntries - Math.pow(average, 2);
-      sumSquares / numberOfEntries  - Math.pow(average, 2)};
+    return new double[] { average, variance };
+  }
+
+  /**
+   * Adds a double to the buffer. If the buffer is full the oldest element is
+   * overwritten.
+   * 
+   * @param value the double to add
+   */
+  public void setNext(double value) {
+    if (index == buffer.length) {
+      index = 0;
+    }
+    buffer[index] = value;
+    index++;
+    if (index == buffer.length) {
+      isFull = true;
+    }
   }
 
   @Override

MyTracks/src/com/google/android/apps/mytracks/stats/TripStatisticsBuilder.java

@@ -20,352 +20,307 @@ import static com.google.android.apps.mytracks.Constants.TAG;
 
 import com.google.android.apps.mytracks.Constants;
 import com.google.android.apps.mytracks.util.PreferencesUtils;
+import com.google.common.annotations.VisibleForTesting;
 
 import android.location.Location;
 import android.util.Log;
 
 /**
- * Statistics keeper for a trip.
+ * Builder for {@link TripStatistics}. For keeping statistics as a track is
+ * paused/resumed and new locations are added.
  * 
  * @author Sandor Dornbush
  * @author Rodrigo Damazio
  */
 public class TripStatisticsBuilder {
-  /**
-   * Statistical data about the trip, which can be displayed to the user.
-   */
-  private final TripStatistics data;
 
-  /**
+  // The trip statistics.
-   * The last location that the gps reported.
+  private final TripStatistics tripStatistics;
-   */
-  private Location lastLocation;
-
-  /**
-   * The last location that contributed to the stats. It is also the last
-   * location the user was found to be moving.
-   */
-  private Location lastMovingLocation;
-
-  /**
-   * The current speed in meters/second as reported by the gps.
-   */
-  private double currentSpeed;
-
-  /**
-   * The current grade. This value is very noisy and not reported to the user.
-   */
-  private double currentGrade;
-
-  /**
-   * Is the trip currently paused?
-   * All trips start paused.
-   */
-  private boolean paused = true;
-
-  /**
-   * A buffer of the last speed readings in meters/second.
-   */
-  private final DoubleBuffer speedBuffer =
-      new DoubleBuffer(Constants.SPEED_SMOOTHING_FACTOR);
-
-  /**
-   * A buffer of the recent elevation readings in meters.
-   */
-  private final DoubleBuffer elevationBuffer =
-      new DoubleBuffer(Constants.ELEVATION_SMOOTHING_FACTOR);
-
-  /**
-   * A buffer of the distance between recent gps readings in meters.
-   */
-  private final DoubleBuffer distanceBuffer =
-      new DoubleBuffer(Constants.DISTANCE_SMOOTHING_FACTOR);
-
-  /**
-   * A buffer of the recent grade calculations.
-   */
-  private final DoubleBuffer gradeBuffer =
-      new DoubleBuffer(Constants.GRADE_SMOOTHING_FACTOR);
-
-  /**
-   * The total number of locations in this trip.
-   */
-  private long totalLocations = 0;
 
+  // The minimum recording distance.
   private int minRecordingDistance = PreferencesUtils.MIN_RECORDING_DISTANCE_DEFAULT;
 
+  // True if the trip is paused. All trips start as paused.
+  private boolean paused = true;
+
+  // The last location as reported by GPS.
+  private Location lastLocation;
+
+  // The last moving location that contributed to the moving statistics.
+  private Location lastMovingLocation;
+
+  // A buffer of the recent speed readings (m/s) for calculating max speed.
+  private final DoubleBuffer speedBuffer = new DoubleBuffer(Constants.SPEED_SMOOTHING_FACTOR);
+
+  // A buffer of the recent elevation readings (m).
+  private final DoubleBuffer elevationBuffer = new DoubleBuffer(
+      Constants.ELEVATION_SMOOTHING_FACTOR);
+
+  // A buffer of the recent distance readings for calculating grade.
+  private final DoubleBuffer distanceBuffer = new DoubleBuffer(Constants.DISTANCE_SMOOTHING_FACTOR);
+
+  // A buffer of the recent grade calculations
+  private final DoubleBuffer gradeBuffer = new DoubleBuffer(Constants.GRADE_SMOOTHING_FACTOR);
+
   /**
-   * Creates a new trip starting at the given time.
+   * Creates a new trip starting at a start time.
    * 
-   * @param startTime the start time.
+   * @param startTime the start time
    */
   public TripStatisticsBuilder(long startTime) {
-    data = new TripStatistics();
+    tripStatistics = new TripStatistics();
     resumeAt(startTime);
   }
 
   /**
-   * Creates a new trip, starting with existing statistics data.
+   * Creates a new trip, starting with an existing {@link TripStatistics}.
    * 
-   * @param statsData the statistics data to copy and start from
+   * @param other the existing {@link TripStatistics}
    */
-  public TripStatisticsBuilder(TripStatistics statsData) {
+  public TripStatisticsBuilder(TripStatistics other) {
-    data = new TripStatistics(statsData);
+    tripStatistics = new TripStatistics(other);
-    if (data.getStartTime() > 0) {
+    if (tripStatistics.getStartTime() > 0) {
-      resumeAt(data.getStartTime());
+      resumeAt(tripStatistics.getStartTime());
     }
   }
 
   /**
-   * Adds a location to the current trip. This will update all of the internal
+   * Sets the min recording distance.
-   * variables with this new location.
    * 
-   * @param currentLocation the current gps location
+   * @param minRecordingDistance the min recording distance
-   * @param systemTime the time used for calculation of totalTime. This should
-   *        be the phone's time (not GPS time)
-   * @return true if the person is moving
    */
-  public boolean addLocation(Location currentLocation, long systemTime) {
+  public void setMinRecordingDistance(int minRecordingDistance) {
-    if (paused) {
+    this.minRecordingDistance = minRecordingDistance;
-      Log.w(TAG,
-          "Tried to account for location while track is paused");
-      return false;
-    }
-
-    totalLocations++;
-
-    double elevationDifference = updateElevation(currentLocation.getAltitude());
-
-    // Update the "instant" values:
-    data.setTotalTime(systemTime - data.getStartTime());
-    currentSpeed = currentLocation.getSpeed();
-
-    // This was the 1st location added, remember it and do nothing else:
-    if (lastLocation == null) {
-      lastLocation = currentLocation;
-      lastMovingLocation = currentLocation;
-      return false;
-    }
-
-    updateBounds(currentLocation);
-
-    // Don't do anything if we didn't move since last fix:
-    double distance = lastLocation.distanceTo(currentLocation);
-    if (distance < minRecordingDistance &&
-        currentSpeed < Constants.MAX_NO_MOVEMENT_SPEED) {
-      lastLocation = currentLocation;
-      return false;
-    }
-
-    data.addTotalDistance(lastMovingLocation.distanceTo(currentLocation));
-    updateSpeed(currentLocation.getTime(), currentSpeed,
-        lastLocation.getTime(), lastLocation.getSpeed());
-
-    updateGrade(distance, elevationDifference);
-    lastLocation = currentLocation;
-    lastMovingLocation = currentLocation;
-    return true;
   }
 
   /**
-   * Updates the track's bounding box to include the given location.
+   * Resumes the current track at a given time.
-   */
-  private void updateBounds(Location location) {
-    data.updateLatitudeExtremities(location.getLatitude());
-    data.updateLongitudeExtremities(location.getLongitude());
-  }
-
-  /**
-   * Updates the elevation measurements.
    * 
-   * @param elevation the current elevation
+   * @param time the time
    */
-  // @VisibleForTesting
+  public void resumeAt(long time) {
-  double updateElevation(double elevation) {
+    if (!paused) {
-    double oldSmoothedElevation = getSmoothedElevation();
-    elevationBuffer.setNext(elevation);
-    double smoothedElevation = getSmoothedElevation();
-    data.updateElevationExtremities(smoothedElevation);
-    double elevationDifference = elevationBuffer.isFull()
-        ? smoothedElevation - oldSmoothedElevation
-        : 0.0;
-    if (elevationDifference > 0) {
-      data.addTotalElevationGain(elevationDifference);
-    }
-    return elevationDifference;
-  }
-
-  /**
-   * Updates the speed measurements.
-   * 
-   * @param updateTime the time of the speed update
-   * @param speed the current speed
-   * @param lastLocationTime the time of the last speed update
-   * @param lastLocationSpeed the speed of the last update
-   */
-  // @VisibleForTesting
-  void updateSpeed(long updateTime, double speed, long lastLocationTime,
-      double lastLocationSpeed) {
-    // We are now sure the user is moving.
-    long timeDifference = updateTime - lastLocationTime;
-    if (timeDifference < 0) {
-      Log.e(TAG,
-          "Found negative time change: " + timeDifference);
-    }
-    data.addMovingTime(timeDifference);
-
-    if (isValidSpeed(updateTime, speed, lastLocationTime, lastLocationSpeed,
-        speedBuffer)) {
-      speedBuffer.setNext(speed);
-      if (speed > data.getMaxSpeed()) {
-        data.setMaxSpeed(speed);
-      }
-      double movingSpeed = data.getAverageMovingSpeed();
-      if (speedBuffer.isFull() && (movingSpeed > data.getMaxSpeed())) {
-        data.setMaxSpeed(movingSpeed);
-      }
-    } else {
-      Log.d(TAG,
-          "TripStatistics ignoring big change: Raw Speed: " + speed
-          + " old: " + lastLocationSpeed + " [" + toString() + "]");
-    }
-  }
-
-  /**
-   * Checks to see if this is a valid speed.
-   * 
-   * @param updateTime The time at the current reading
-   * @param speed The current speed
-   * @param lastLocationTime The time at the last location
-   * @param lastLocationSpeed Speed at the last location
-   * @param speedBuffer A buffer of recent readings
-   * @return True if this is likely a valid speed
-   */
-  public static boolean isValidSpeed(long updateTime, double speed,
-      long lastLocationTime, double lastLocationSpeed,
-      DoubleBuffer speedBuffer) {
-
-    // We don't want to count 0 towards the speed.
-    if (speed == 0) {
-      return false;
-    }
-    // We are now sure the user is moving.
-    long timeDifference = updateTime - lastLocationTime;
-
-    // There are a lot of noisy speed readings.
-    // Do the cheapest checks first, most expensive last.
-    // The following code will ignore unlikely to be real readings.
-    // - 128 m/s seems to be an internal android error code.
-    if (Math.abs(speed - 128) < 1) {
-      return false;
-    }
-
-    // Another check for a spurious reading. See if the path seems physically
-    // likely. Ignore any speeds that imply accelaration greater than 2g's
-    // Really who can accelerate faster?
-    double speedDifference = Math.abs(lastLocationSpeed - speed);
-    if (speedDifference > Constants.MAX_ACCELERATION * timeDifference) {
-      return false;
-    }
-
-    // There are three additional checks if the reading gets this far:
-    // - Only use the speed if the buffer is full
-    // - Check that the current speed is less than 10x the recent smoothed speed
-    // - Double check that the current speed does not imply crazy acceleration
-    double smoothedSpeed = speedBuffer.getAverage();
-    double smoothedDiff = Math.abs(smoothedSpeed - speed);
-    return !speedBuffer.isFull() ||
-        (speed < smoothedSpeed * 10
-         && smoothedDiff < Constants.MAX_ACCELERATION * timeDifference);
-  }
-
-  /**
-   * Updates the grade measurements.
-   * 
-   * @param distance the distance the user just traveled
-   * @param elevationDifference the elevation difference between the current
-   *        reading and the previous reading
-   */
-  // @VisibleForTesting
-  void updateGrade(double distance, double elevationDifference) {
-    distanceBuffer.setNext(distance);
-    double smoothedDistance = distanceBuffer.getAverage();
-
-    // With the error in the altitude measurement it is dangerous to divide
-    // by anything less than 5.
-    if (!elevationBuffer.isFull() || !distanceBuffer.isFull()
-        || smoothedDistance < 5.0) {
       return;
     }
-    currentGrade = elevationDifference / smoothedDistance;
+
-    gradeBuffer.setNext(currentGrade);
+    tripStatistics.setStartTime(time);
-    data.updateGradeExtremities(gradeBuffer.getAverage());
+    tripStatistics.setStopTime(-1L);
+    paused = false;
+    lastLocation = null;
+    lastMovingLocation = null;
+    speedBuffer.reset();
+    elevationBuffer.reset();
+    distanceBuffer.reset();
+    gradeBuffer.reset();
   }
 
   /**
-   * Pauses the track at the given time.
+   * Pauses the track at a given time.
    * 
    * @param time the time to pause at
    */
   public void pauseAt(long time) {
-    if (paused) { return; }
+    if (paused) {
-
+      return;
-    data.setStopTime(time);
+    }
-    data.setTotalTime(time - data.getStartTime());
+    tripStatistics.setStopTime(time);
-    lastLocation = null; // Make sure the counter restarts.
+    // TODO: total time needs to take into account pauses
+    tripStatistics.setTotalTime(time - tripStatistics.getStartTime());
     paused = true;
   }
 
   /**
-   * Resumes the current track at the given time.
+   * Gets the trip statistics.
-   *
-   * @param time the time to resume at
    */
-  public void resumeAt(long time) {
+  public TripStatistics getTripStatistics() {
-    if (!paused) { return; }
+    // Take a snapshot - we don't want anyone messing with our internals
-
+    return new TripStatistics(tripStatistics);
-    // TODO: The times are bogus if the track is paused then resumed again
-    data.setStartTime(time);
-    data.setStopTime(-1);
-    paused = false;
-  }
-
-  @Override
-  public String toString() {
-    return "TripStatistics { Data: " + data.toString()
-         + "; Total Locations: " + totalLocations
-         + "; Paused: " + paused
-         + "; Current speed: " + currentSpeed
-         + "; Current grade: " + currentGrade
-         + "}";
   }
 
   /**
-   * Returns the amount of time the user has been idle or 0 if they are moving.
+   * Returns the amount of time the user has been idle or 0 if he is moving.
    */
   public long getIdleTime() {
-    if (lastLocation == null || lastMovingLocation == null)
+    if (lastLocation == null || lastMovingLocation == null) {
       return 0;
+    }
     return lastLocation.getTime() - lastMovingLocation.getTime();
   }
 
   /**
-   * Gets the current elevation smoothed over several readings. The elevation
+   * Gets the smoothed elevation over several readings. The elevation readings
-   * data is very noisy so it is better to use the smoothed elevation than the
+   * is noisy so the smoothed elevation is better than the raw elevation for
-   * raw elevation for many tasks.
+   * many tasks.
-   * 
-   * @return The elevation smoothed over several readings
    */
   public double getSmoothedElevation() {
     return elevationBuffer.getAverage();
   }
 
-  public TripStatistics getStatistics() {
+  /**
-    // Take a snapshot - we don't want anyone messing with our internals
+   * Adds a location. This will update all of the internal variables with this
-    return new TripStatistics(data);
+   * new location.
+   * 
+   * @param location the location
+   * @param systemTime the system time for calculating totalTime. This should be
+   *          the phone's system time (not GPS time)
+   * @return true if the person is moving
+   */
+  public boolean addLocation(Location location, long systemTime) {
+    if (paused) {
+      Log.w(TAG, "Track is paused. Ignore addLocation.");
+      return false;
+    }
+
+    tripStatistics.setTotalTime(systemTime - tripStatistics.getStartTime());
+
+    double elevationDifference = updateElevation(location.getAltitude());
+    tripStatistics.updateLatitudeExtremities(location.getLatitude());
+    tripStatistics.updateLongitudeExtremities(location.getLongitude());
+
+    // If this is the first location, remember it and return.
+    if (lastLocation == null || lastMovingLocation == null) {
+      lastLocation = location;
+      lastMovingLocation = location;
+      return false;
+    }
+
+    // Don't do anything more if we didn't move since the last location.
+    double distance = lastLocation.distanceTo(location);
+    if (distance < minRecordingDistance && location.getSpeed() < Constants.MAX_NO_MOVEMENT_SPEED) {
+      lastLocation = location;
+      return false;
+    }
+
+    long timeDifference = location.getTime() - lastLocation.getTime();
+    if (timeDifference < 0) {
+      Log.e(TAG, "Negative time difference: " + timeDifference);
+      lastLocation = location;
+      return false;
+    }
+
+    tripStatistics.addTotalDistance(lastMovingLocation.distanceTo(location));
+    tripStatistics.addMovingTime(timeDifference);
+    updateSpeed(
+        location.getTime(), location.getSpeed(), lastLocation.getTime(), lastLocation.getSpeed());
+    updateGrade(distance, elevationDifference);
+    lastLocation = location;
+    lastMovingLocation = location;
+    return true;
   }
 
-  public void setMinRecordingDistance(int minRecordingDistance) {
+  /**
-    this.minRecordingDistance = minRecordingDistance;
+   * Updates a speed reading. Assumes the user is moving.
+   * 
+   * @param time the time
+   * @param speed the speed
+   * @param lastLocationTime the last location time
+   * @param lastLocationSpeed the last location speed
+   */
+  @VisibleForTesting
+  void updateSpeed(long time, double speed, long lastLocationTime, double lastLocationSpeed) {
+    if (!isValidSpeed(time, speed, lastLocationTime, lastLocationSpeed, speedBuffer)) {
+      Log.d(TAG, "Invalid speed. speed: " + speed + " lastLocationSpeed: " + lastLocationSpeed);
+      return;
+    }
+    speedBuffer.setNext(speed);
+    if (speed > tripStatistics.getMaxSpeed()) {
+      tripStatistics.setMaxSpeed(speed);
+    }
+    double movingSpeed = tripStatistics.getAverageMovingSpeed();
+    if (speedBuffer.isFull() && movingSpeed > tripStatistics.getMaxSpeed()) {
+      tripStatistics.setMaxSpeed(movingSpeed);
+    }
+  }
+
+  /**
+   * Updates an elevation reading.
+   * 
+   * @param elevation the elevation
+   */
+  @VisibleForTesting
+  double updateElevation(double elevation) {
+    double oldAverage = elevationBuffer.getAverage();
+    elevationBuffer.setNext(elevation);
+    double newAverage = elevationBuffer.getAverage();
+    tripStatistics.updateElevationExtremities(newAverage);
+    double elevationDifference = elevationBuffer.isFull() ? newAverage - oldAverage : 0.0;
+    if (elevationDifference > 0) {
+      tripStatistics.addTotalElevationGain(elevationDifference);
+    }
+    return elevationDifference;
+  }
+
+  /**
+   * Updates a grade reading.
+   * 
+   * @param distance the distance the user just traveled
+   * @param elevationDifference the elevation difference between the current
+   *          reading and the previous reading
+   */
+  @VisibleForTesting
+  void updateGrade(double distance, double elevationDifference) {
+    distanceBuffer.setNext(distance);
+    double smoothedDistance = distanceBuffer.getAverage();
+
+    /*
+     * With the error in the altitude measurement it is dangerous to divide by
+     * anything less than 5.
+     */
+    if (!elevationBuffer.isFull() || !distanceBuffer.isFull() || smoothedDistance < 5.0) {
+      return;
+    }
+    gradeBuffer.setNext(elevationDifference / smoothedDistance);
+    tripStatistics.updateGradeExtremities(gradeBuffer.getAverage());
+  }
+
+  /**
+   * Returns true if the speed is valid.
+   * 
+   * @param time the time
+   * @param speed the speed
+   * @param lastLocationTime the last location time
+   * @param lastLocationSpeed the last location speed
+   * @param speedBuffer a buffer of speed readings
+   */
+  public static boolean isValidSpeed(long time, double speed, long lastLocationTime,
+      double lastLocationSpeed, DoubleBuffer speedBuffer) {
+
+    /*
+     * There are a lot of noisy speed readings. Do the cheapest checks first,
+     * most expensive last.
+     */
+    if (speed == 0) {
+      return false;
+    }
+
+    /*
+     * The following code will ignore unlikely readings. 128 m/s seems to be an
+     * internal android error code.
+     */
+    if (Math.abs(speed - 128) < 1) {
+      return false;
+    }
+
+    /*
+     * See if the speed seems physically likely. Ignore any speeds that imply
+     * acceleration greater than 2g.
+     */
+    long timeDifference = time - lastLocationTime;
+    double speedDifference = Math.abs(lastLocationSpeed - speed);
+    if (speedDifference > Constants.MAX_ACCELERATION * timeDifference) {
+      return false;
+    }
+
+    /*
+     * Only check if the speed buffer is full. Check that the speed is less than
+     * 10X the smoothed average and the speed difference doesn't imply 2g
+     * acceleration.
+     */
+    if (!speedBuffer.isFull()) {
+      return true;
+    }
+    double average = speedBuffer.getAverage();
+    double diff = Math.abs(average - speed);
+    return (speed < average * 10) && (diff < Constants.MAX_ACCELERATION * timeDifference);
   }
 }

MyTracksLib/src/com/google/android/apps/mytracks/stats/ExtremityMonitor.java

@@ -23,14 +23,10 @@ package com.google.android.apps.mytracks.stats;
  */
 public class ExtremityMonitor {
 
-  /**
+  // The smallest value seen so far.
-   * The smallest value seen so far.
-   */
   private double min;
 
-  /**
+  // The largest value seen so far.
-   * The largest value seen so far.
-   */
   private double max;
 
   public ExtremityMonitor() {
@@ -38,9 +34,31 @@ public class ExtremityMonitor {
   }
 
   /**
-   * Updates the min and the max with the new value.
+   * Resets this object to it's initial state where the min and max are unknown.
+   */
+  public void reset() {
+    min = Double.POSITIVE_INFINITY;
+    max = Double.NEGATIVE_INFINITY;
+  }
+
+  /**
+   * Gets the minimum value seen.
+   */
+  public double getMin() {
+    return min;
+  }
+
+  /**
+   * Gets the maximum value seen.
+   */
+  public double getMax() {
+    return max;
+  }
+
+  /**
+   * Updates the min and the max with a new value.
    * 
-   * @param value the new value for the monitor
+   * @param value the new value
    * @return true if an extremity was found
    */
   public boolean update(double value) {
@@ -56,34 +74,11 @@ public class ExtremityMonitor {
     return changed;
   }
 
-  /**
-   * Gets the minimum value seen.
-   *
-   * @return The minimum value passed into the update() function
-   */
-  public double getMin() {
-    return min;
-  }
-
-  /**
-   * Gets the maximum value seen.
-   *
-   * @return The maximum value passed into the update() function
-   */
-  public double getMax() {
-    return max;
-  }
-
-  /**
-   * Resets this object to it's initial state where the min and max are unknown.
-   */
-  public void reset() {
-    min = Double.POSITIVE_INFINITY;
-    max = Double.NEGATIVE_INFINITY;
-  }
-
   /**
    * Sets the minimum and maximum values.
+   * 
+   * @param min the minimum value
+   * @param max the maximum value
    */
   public void set(double min, double max) {
     this.min = min;
@@ -92,6 +87,8 @@ public class ExtremityMonitor {
 
   /**
    * Sets the minimum value.
+   * 
+   * @param min the minimum value
    */
   public void setMin(double min) {
     this.min = min;
@@ -99,14 +96,18 @@ public class ExtremityMonitor {
 
   /**
    * Sets the maximum value.
+   * 
+   * @param max the maximum value
    */
   public void setMax(double max) {
     this.max = max;
   }
 
+  /**
+   * Returns true if has data.
+   */
   public boolean hasData() {
-    return min != Double.POSITIVE_INFINITY
+    return min != Double.POSITIVE_INFINITY && max != Double.NEGATIVE_INFINITY;
-        && max != Double.NEGATIVE_INFINITY;
   }
 
   @Override

MyTracksLib/src/com/google/android/apps/mytracks/stats/TripStatistics.java

@@ -13,85 +13,59 @@
  * License for the specific language governing permissions and limitations under
  * the License.
  */
+
 package com.google.android.apps.mytracks.stats;
 
 import android.os.Parcel;
 import android.os.Parcelable;
 
 /**
- * Statistical data about a trip.
+ * Statistical data about a trip. The data in this class should be filled out by
- * The data in this class should be filled out by TripStatisticsBuilder.
+ * TripStatisticsBuilder.
- *
+ * <p>
  * TODO: hashCode and equals
  * 
  * @author Rodrigo Damazio
  */
 public class TripStatistics implements Parcelable {
 
-  /**
+  // The trip start time. This is the system time, might not match the GPs time.
-   * The start time for the trip. This is system time which might not match gps
-   * time.
-   */
   private long startTime = -1L;
 
-  /**
+  // The trip stop time. This is the system time, might not match the GPS time.
-   * The stop time for the trip. This is the system time which might not match
-   * gps time.
-   */
   private long stopTime = -1L;
 
-  /**
+  // The total trip distance (meters).
-   * The total time that we believe the user was traveling in milliseconds.
-   */
-  private long movingTime;
-
-  /**
-   * The total time of the trip in milliseconds.
-   * This is only updated when new points are received, so it may be stale.
-   */
-  private long totalTime;
-
-  /**
-   * The total distance in meters that the user traveled on this trip.
-   */
   private double totalDistance;
 
-  /**
+  // The total time (ms). Updated when new points are received, may be stale.
-   * The total elevation gained on this trip in meters.
+  private long totalTime;
-   */
-  private double totalElevationGain;
 
-  /**
+  // The total moving time (ms). Based on when we believe the user is traveling.
-   * The maximum speed in meters/second reported that we believe to be a valid
+  private long movingTime;
-   * speed.
-   */
-  private double maxSpeed;
 
-  /**
+  // The min and max latitude seen in this trip.
-   * The min and max latitude values seen in this trip.
-   */
   private final ExtremityMonitor latitudeExtremities = new ExtremityMonitor();
 
-  /**
+  // The min and max longitude seen in this trip.
-   * The min and max longitude values seen in this trip.
-   */
   private final ExtremityMonitor longitudeExtremities = new ExtremityMonitor();
 
-  /**
+  // The maximum speed (meters/second) that we believe is valid.
-   * The min and max elevation seen on this trip in meters.
+  private double maxSpeed;
-   */
+
+  // The min and max elevation (meters) seen on this trip.
   private final ExtremityMonitor elevationExtremities = new ExtremityMonitor();
 
-  /**
+  // The total elevation gained (meters).
-   * The minimum and maximum grade calculations on this trip.
+  private double totalElevationGain;
-   */
+
+  // The min and max grade seen on this trip.
   private final ExtremityMonitor gradeExtremities = new ExtremityMonitor();
 
   /**
    * Default constructor.
    */
-  public TripStatistics() {
+  public TripStatistics() {}
-  }
 
   /**
    * Copy constructor.
@@ -99,96 +73,166 @@ public class TripStatistics implements Parcelable {
    * @param other another statistics data object to copy from
    */
   public TripStatistics(TripStatistics other) {
-    this.maxSpeed = other.maxSpeed;
-    this.movingTime = other.movingTime;
     this.startTime = other.startTime;
     this.stopTime = other.stopTime;
     this.totalDistance = other.totalDistance;
-    this.totalElevationGain = other.totalElevationGain;
     this.totalTime = other.totalTime;
-
+    this.movingTime = other.movingTime;
-    this.latitudeExtremities.set(other.latitudeExtremities.getMin(),
+    this.latitudeExtremities.set(
-                                 other.latitudeExtremities.getMax());
+        other.latitudeExtremities.getMin(), other.latitudeExtremities.getMax());
-    this.longitudeExtremities.set(other.longitudeExtremities.getMin(),
+    this.longitudeExtremities.set(
-                                  other.longitudeExtremities.getMax());
+        other.longitudeExtremities.getMin(), other.longitudeExtremities.getMax());
-    this.elevationExtremities.set(other.elevationExtremities.getMin(),
+    this.maxSpeed = other.maxSpeed;
-                                  other.elevationExtremities.getMax());
+    this.elevationExtremities.set(
-    this.gradeExtremities.set(other.gradeExtremities.getMin(),
+        other.elevationExtremities.getMin(), other.elevationExtremities.getMax());
-                              other.gradeExtremities.getMax());
+    this.totalElevationGain = other.totalElevationGain;
+    this.gradeExtremities.set(other.gradeExtremities.getMin(), other.gradeExtremities.getMax());
   }
 
   /**
-   * Combines these statistics with those from another object.
+   * Combines these statistics with those from another object. This assumes that
-   * This assumes that the time periods covered by each do not intersect.
+   * the time periods covered by each do not intersect.
    * 
-   * @param other the other waypoint
+   * @param other another statistics data object
    */
   public void merge(TripStatistics other) {
     startTime = Math.min(startTime, other.startTime);
     stopTime = Math.max(stopTime, other.stopTime);
+    totalDistance += other.totalDistance;
     totalTime += other.totalTime;
     movingTime += other.movingTime;
-    totalDistance += other.totalDistance;
-    totalElevationGain += other.totalElevationGain;
-    maxSpeed = Math.max(maxSpeed, other.maxSpeed);
-
-    latitudeExtremities.update(other.latitudeExtremities.getMax());
     latitudeExtremities.update(other.latitudeExtremities.getMin());
-    longitudeExtremities.update(other.longitudeExtremities.getMax());
+    latitudeExtremities.update(other.latitudeExtremities.getMax());
     longitudeExtremities.update(other.longitudeExtremities.getMin());
-    elevationExtremities.update(other.elevationExtremities.getMax());
+    longitudeExtremities.update(other.longitudeExtremities.getMax());
+    maxSpeed = Math.max(maxSpeed, other.maxSpeed);
     elevationExtremities.update(other.elevationExtremities.getMin());
-    gradeExtremities.update(other.gradeExtremities.getMax());
+    elevationExtremities.update(other.elevationExtremities.getMax());
+    totalElevationGain += other.totalElevationGain;
     gradeExtremities.update(other.gradeExtremities.getMin());
+    gradeExtremities.update(other.gradeExtremities.getMax());
   }
 
   /**
-   * Gets the time that this track started.
+   * Gets the trip start time. The number of milliseconds since epoch.
-   *
-   * @return The number of milliseconds since epoch to the time when this track
-   *         started
    */
   public long getStartTime() {
     return startTime;
   }
 
   /**
-   * Gets the time that this track stopped.
+   * Gets the trip stop time. The number of milliseconds since epoch.
-   *
-   * @return The number of milliseconds since epoch to the time when this track
-   *         stopped
    */
   public long getStopTime() {
     return stopTime;
   }
 
   /**
-   * Gets the total time that this track has been active.
+   * Gets the total distance the user traveled in meters.
-   * This statistic is only updated when a new point is added to the statistics,
-   * so it may be off. If you need to calculate the proper total time, use
-   * {@link #getStartTime} with the current time.
-   *
-   * @return The total number of milliseconds the track was active
-   */
-  public long getTotalTime() {
-    return totalTime;
-  }
-
-  /**
-   * Gets the total distance the user traveled.
-   *
-   * @return The total distance traveled in meters
    */
   public double getTotalDistance() {
     return totalDistance;
   }
 
   /**
-   * Gets the the average speed the user traveled.
+   * Gets the total time in milliseconds that this track has been active. This
-   * This calculation only takes into account the displacement until the last
+   * statistic is only updated when a new point is added to the statistics, so
-   * point that was accounted for in statistics.
+   * it may be off. If you need to calculate the proper total time, use
-   *
+   * {@link #getStartTime} with the current time.
-   * @return The average speed in m/s
+   */
+  public long getTotalTime() {
+    return totalTime;
+  }
+
+  /**
+   * Gets the moving time in milliseconds.
+   */
+  public long getMovingTime() {
+    return movingTime;
+  }
+
+  /**
+   * Gets the topmost position (highest latitude) of the track, in signed
+   * degrees.
+   */
+  public double getTopDegrees() {
+    return latitudeExtremities.getMax();
+  }
+
+  /**
+   * Gets the topmost position (highest latitude) of the track, in signed
+   * millions of degrees.
+   */
+  public int getTop() {
+    return (int) (latitudeExtremities.getMax() * 1E6);
+  }
+
+  /**
+   * Gets the bottommost position (lowest latitude) of the track, in signed
+   * degrees.
+   */
+  public double getBottomDegrees() {
+    return latitudeExtremities.getMin();
+  }
+
+  /**
+   * Gets the bottommost position (lowest latitude) of the track, in signed
+   * millions of degrees.
+   */
+  public int getBottom() {
+    return (int) (latitudeExtremities.getMin() * 1E6);
+  }
+
+  /**
+   * Gets the leftmost position (lowest longitude) of the track, in signed
+   * degrees.
+   */
+  public double getLeftDegrees() {
+    return longitudeExtremities.getMin();
+  }
+
+  /**
+   * Gets the leftmost position (lowest longitude) of the track, in signed
+   * millions of degrees.
+   */
+  public int getLeft() {
+    return (int) (longitudeExtremities.getMin() * 1E6);
+  }
+
+  /**
+   * Gets the rightmost position (highest longitude) of the track, in signed
+   * degrees.
+   */
+  public double getRightDegrees() {
+    return longitudeExtremities.getMax();
+  }
+
+  /**
+   * Gets the rightmost position (highest longitude) of the track, in signed
+   * millions of degrees.
+   */
+  public int getRight() {
+    return (int) (longitudeExtremities.getMax() * 1E6);
+  }
+
+  /**
+   * Gets the mean latitude position of the track, in signed degrees.
+   */
+  public double getMeanLatitude() {
+    return (getBottomDegrees() + getTopDegrees()) / 2.0;
+  }
+
+  /**
+   * Gets the mean longitude position of the track, in signed degrees.
+   */
+  public double getMeanLongitude() {
+    return (getLeftDegrees() + getRightDegrees()) / 2.0;
+  }
+
+  /**
+   * Gets the average speed in meters/second. This calculation only takes into
+   * account the displacement until the last point that was accounted for in
+   * statistics.
    */
   public double getAverageSpeed() {
     if (totalTime == 0L) {
@@ -198,10 +242,7 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Gets the the average speed the user traveled when they were actively
+   * Gets the average moving speed in meters/second.
-   * moving.
-   *
-   * @return The average moving speed in m/s
    */
   public double getAverageMovingSpeed() {
     if (movingTime == 0L) {
@@ -211,179 +252,68 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Gets the the maximum speed for this track.
+   * Gets the maximum speed in meters/second.
-   *
-   * @return The maximum speed in m/s
    */
   public double getMaxSpeed() {
     return maxSpeed;
   }
 
   /**
-   * Gets the moving time.
+   * Gets the minimum elevation. This is calculated from the smoothed elevation
-   *
+   * so this can actually be more than the current elevation.
-   * @return The total number of milliseconds the user was moving
-   */
-  public long getMovingTime() {
-    return movingTime;
-  }
-
-  /**
-   * Gets the total elevation gain for this trip. This is calculated as the sum
-   * of all positive differences in the smoothed elevation.
-   *
-   * @return The elevation gain in meters for this trip
-   */
-  public double getTotalElevationGain() {
-    return totalElevationGain;
-  }
-
-  /**
-   * Returns the leftmost position (lowest longitude) of the track, in signed degrees.
-   */
-  public double getLeftDegrees() {
-    return longitudeExtremities.getMin();
-  }
-
-  /**
-   * Returns the leftmost position (lowest longitude) of the track, in signed millions of degrees.
-   */
-  public int getLeft() {
-    return (int) (longitudeExtremities.getMin() * 1E6);
-  }
-
-  /**
-   * Returns the rightmost position (highest longitude) of the track, in signed degrees.
-   */
-  public double getRightDegrees() {
-    return longitudeExtremities.getMax();
-  }
-
-  /**
-   * Returns the rightmost position (highest longitude) of the track, in signed millions of degrees.
-   */
-  public int getRight() {
-    return (int) (longitudeExtremities.getMax() * 1E6);
-  }
-
-  /**
-   * Returns the bottommost position (lowest latitude) of the track, in signed degrees.
-   */
-  public double getBottomDegrees() {
-    return latitudeExtremities.getMin();
-  }
-
-  /**
-   * Returns the bottommost position (lowest latitude) of the track, in signed millions of degrees.
-   */
-  public int getBottom() {
-    return (int) (latitudeExtremities.getMin() * 1E6);
-  }
-
-  /**
-   * Returns the topmost position (highest latitude) of the track, in signed degrees.
-   */
-  public double getTopDegrees() {
-    return latitudeExtremities.getMax();
-  }
-
-  /**
-   * Returns the topmost position (highest latitude) of the track, in signed millions of degrees.
-   */
-  public int getTop() {
-    return (int) (latitudeExtremities.getMax() * 1E6);
-  }
-
-  /**
-   * Returns the mean position (center latitude) of the track, in signed degrees.
-   */
-  public double getMeanLatitude() {
-    return (getBottomDegrees() + getTopDegrees()) / 2.0;
-  }
-
-  /**
-   * Returns the mean position (center longitude) of the track, in signed degrees.
-   */
-  public double getMeanLongitude() {
-    return (getLeftDegrees() + getRightDegrees()) / 2.0;
-  }
-
-  /**
-   * Gets the minimum elevation seen on this trip. This is calculated from the
-   * smoothed elevation so this can actually be more than the current elevation.
-   *
-   * @return The smallest elevation reading for this trip in meters
    */
   public double getMinElevation() {
     return elevationExtremities.getMin();
   }
 
   /**
-   * Gets the maximum elevation seen on this trip. This is calculated from the
+   * Gets the maximum elevation. This is calculated from the smoothed elevation
-   * smoothed elevation so this can actually be less than the current elevation.
+   * so this can actually be less than the current elevation.
-   *
-   * @return The largest elevation reading for this trip in meters
    */
   public double getMaxElevation() {
     return elevationExtremities.getMax();
   }
 
+  /**
+   * Gets the total elevation gain in meters. This is calculated as the sum of
+   * all positive differences in the smoothed elevation.
+   */
+  public double getTotalElevationGain() {
+    return totalElevationGain;
+  }
+
+  /**
+   * Gets the minimum grade for this trip.
+   */
+  public double getMinGrade() {
+    return gradeExtremities.getMin();
+  }
+
   /**
    * Gets the maximum grade for this trip.
-   *
-   * @return The maximum grade for this trip as a fraction
    */
   public double getMaxGrade() {
     return gradeExtremities.getMax();
   }
 
   /**
-   * Gets the minimum grade for this trip.
+   * Sets the trip start time.
    * 
-   * @return The minimum grade for this trip as a fraction
+   * @param startTime the trip start time in milliseconds since the epoch
-   */
-  public double getMinGrade() {
-    return gradeExtremities.getMin();
-  }
-
-  // Setters - to be used when restoring state or loading from the DB
-
-  /**
-   * Sets the start time for this trip.
-   *
-   * @param startTime the start time, in milliseconds since the epoch
    */
   public void setStartTime(long startTime) {
     this.startTime = startTime;
   }
 
   /**
-   * Sets the stop time for this trip.
+   * Sets the trip stop time.
    * 
-   * @param stopTime the stop time, in milliseconds since the epoch
+   * @param stopTime the stop time in milliseconds since the epoch
    */
   public void setStopTime(long stopTime) {
     this.stopTime = stopTime;
   }
 
-  /**
-   * Sets the total moving time.
-   *
-   * @param movingTime the moving time in milliseconds
-   */
-  public void setMovingTime(long movingTime) {
-    this.movingTime = movingTime;
-  }
-
-  /**
-   * Sets the total trip time.
-   *
-   * @param totalTime the total trip time in milliseconds
-   */
-  public void setTotalTime(long totalTime) {
-    this.totalTime = totalTime;
-  }
-
   /**
    * Sets the total trip distance.
    * 
@@ -393,76 +323,6 @@ public class TripStatistics implements Parcelable {
     this.totalDistance = totalDistance;
   }
 
-  /**
-   * Sets the total elevation variation during the trip.
-   *
-   * @param totalElevationGain the elevation variation in meters
-   */
-  public void setTotalElevationGain(double totalElevationGain) {
-    this.totalElevationGain = totalElevationGain;
-  }
-
-  /**
-   * Sets the maximum speed reached during the trip.
-   *
-   * @param maxSpeed the maximum speed in meters per second
-   */
-  public void setMaxSpeed(double maxSpeed) {
-    this.maxSpeed = maxSpeed;
-  }
-
-  /**
-   * Sets the minimum elevation reached during the trip.
-   *
-   * @param elevation the minimum elevation in meters
-   */
-  public void setMinElevation(double elevation) {
-    elevationExtremities.setMin(elevation);
-  }
-
-  /**
-   * Sets the maximum elevation reached during the trip.
-   *
-   * @param elevation the maximum elevation in meters
-   */
-  public void setMaxElevation(double elevation) {
-    elevationExtremities.setMax(elevation);
-  }
-
-  /**
-   * Sets the minimum grade obtained during the trip.
-   *
-   * @param grade the grade as a fraction (-1.0 would mean vertical downwards)
-   */
-  public void setMinGrade(double grade) {
-    gradeExtremities.setMin(grade);
-  }
-
-  /**
-   * Sets the maximum grade obtained during the trip).
-   *
-   * @param grade the grade as a fraction (1.0 would mean vertical upwards)
-   */
-  public void setMaxGrade(double grade) {
-    gradeExtremities.setMax(grade);
-  }
-
-  /**
-   * Sets the bounding box for this trip.
-   * The unit for all parameters is signed decimal degrees (degrees * 1E6).
-   *
-   * @param leftE6 the westmost longitude reached
-   * @param topE6 the northmost latitude reached
-   * @param rightE6 the eastmost longitude reached
-   * @param bottomE6 the southmost latitude reached
-   */
-  public void setBounds(int leftE6, int topE6, int rightE6, int bottomE6) {
-    latitudeExtremities.set(bottomE6 / 1E6, topE6 / 1E6);
-    longitudeExtremities.set(leftE6 / 1E6, rightE6 / 1E6);
-  }
-
-  // Data manipulation methods
-
   /**
    * Adds to the current total distance.
    * 
@@ -473,16 +333,25 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Adds to the total elevation variation.
+   * Sets the trip total time.
    * 
-   * @param gain the elevation variation in meters
+   * @param totalTime the trip total time in milliseconds
    */
-  void addTotalElevationGain(double gain) {
+  public void setTotalTime(long totalTime) {
-    totalElevationGain += gain;
+    this.totalTime = totalTime;
   }
 
   /**
-   * Adds to the total moving time of the trip.
+   * Sets the trip total moving time.
+   * 
+   * @param movingTime the trip total moving time in milliseconds
+   */
+  public void setMovingTime(long movingTime) {
+    this.movingTime = movingTime;
+  }
+
+  /**
+   * Adds to the trip total moving time.
    * 
    * @param time the time in milliseconds
    */
@@ -491,7 +360,21 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Accounts for a new latitude value for the bounding box.
+   * Sets the bounding box for this trip. The unit for all parameters is signed
+   * millions of degree (degrees * 1E6).
+   * 
+   * @param leftE6 the leftmost longitude reached
+   * @param topE6 the topmost latitude reached
+   * @param rightE6 the rightmost longitude reached
+   * @param bottomE6 the bottommost latitude reached
+   */
+  public void setBounds(int leftE6, int topE6, int rightE6, int bottomE6) {
+    latitudeExtremities.set(bottomE6 / 1E6, topE6 / 1E6);
+    longitudeExtremities.set(leftE6 / 1E6, rightE6 / 1E6);
+  }
+
+  /**
+   * Updates a new latitude value.
    * 
    * @param latitude the latitude value in signed decimal degrees
    */
@@ -500,7 +383,7 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Accounts for a new longitude value for the bounding box.
+   * Updates a new longitude value.
    * 
    * @param longitude the longitude value in signed decimal degrees
    */
@@ -509,7 +392,34 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Accounts for a new elevation value for the bounding box.
+   * Sets the maximum speed.
+   * 
+   * @param maxSpeed the maximum speed in meters/second
+   */
+  public void setMaxSpeed(double maxSpeed) {
+    this.maxSpeed = maxSpeed;
+  }
+
+  /**
+   * Sets the minimum elevation.
+   * 
+   * @param elevation the minimum elevation in meters
+   */
+  public void setMinElevation(double elevation) {
+    elevationExtremities.setMin(elevation);
+  }
+
+  /**
+   * Sets the maximum elevation.
+   * 
+   * @param elevation the maximum elevation in meters
+   */
+  public void setMaxElevation(double elevation) {
+    elevationExtremities.setMax(elevation);
+  }
+
+  /**
+   * Updates a new elevation.
    * 
    * @param elevation the elevation value in meters
    */
@@ -518,7 +428,43 @@ public class TripStatistics implements Parcelable {
   }
 
   /**
-   * Accounts for a new grade value.
+   * Sets the total elevation gain.
+   * 
+   * @param totalElevationGain the elevation gain in meters
+   */
+  public void setTotalElevationGain(double totalElevationGain) {
+    this.totalElevationGain = totalElevationGain;
+  }
+
+  /**
+   * Adds to the total elevation gain.
+   * 
+   * @param gain the elevation gain in meters
+   */
+  void addTotalElevationGain(double gain) {
+    totalElevationGain += gain;
+  }
+
+  /**
+   * Sets the minimum grade.
+   * 
+   * @param grade the grade as a fraction (-1.0 would mean vertical downwards)
+   */
+  public void setMinGrade(double grade) {
+    gradeExtremities.setMin(grade);
+  }
+
+  /**
+   * Sets the maximum grade.
+   * 
+   * @param grade the grade as a fraction (1.0 would mean vertical upwards)
+   */
+  public void setMaxGrade(double grade) {
+    gradeExtremities.setMax(grade);
+  }
+
+  /**
+   * Updates a new grade value.
    * 
    * @param grade the grade value as a fraction
    */
@@ -526,41 +472,33 @@ public class TripStatistics implements Parcelable {
     gradeExtremities.update(grade);
   }
 
-  // String conversion
-
   @Override
   public String toString() {
-    return "TripStatistics { Start Time: " + getStartTime()
+    return "TripStatistics { Start Time: " + getStartTime() + "; Stop Time: " + getStopTime()
-        + "; Total Time: " + getTotalTime()
+        + "; Total Time: " + getTotalTime() + "; Total Distance: " + getTotalDistance()
-        + "; Moving Time: " + getMovingTime()
+        + "; Total Time: " + getTotalTime() + "; Moving Time: " + getMovingTime()
-        + "; Total Distance: " + getTotalDistance()
+        + "; Min Latitude: " + getBottomDegrees() + "; Max Latitude: " + getTopDegrees()
-        + "; Elevation Gain: " + getTotalElevationGain()
+        + "; Min Longitude: " + getLeftDegrees() + "; Max Longitude: " + getRightDegrees()
-        + "; Min Elevation: " + getMinElevation()
+        + "; Max Elevation: " + getMaxElevation() + "; Max Speed: " + getMaxSpeed()
-        + "; Max Elevation: " + getMaxElevation()
+        + "; Min Elevation: " + getMinElevation() + "; Max Elevation: " + getMaxElevation()
-        + "; Average Speed: " + getAverageMovingSpeed()
+        + "; Elevation Gain: " + getTotalElevationGain() + "; Min Grade: " + getMinGrade()
-        + "; Min Grade: " + getMinGrade()
+        + "; Max Grade: " + getMaxGrade() + "}";
-        + "; Max Grade: " + getMaxGrade()
-        + "}";
   }
 
-  // Parcelable interface and creator
-
   /**
    * Creator of statistics data from parcels.
    */
-  public static class Creator
+  public static class Creator implements Parcelable.Creator<TripStatistics> {
-      implements Parcelable.Creator<TripStatistics> {
 
     @Override
     public TripStatistics createFromParcel(Parcel source) {
       TripStatistics data = new TripStatistics();
 
       data.startTime = source.readLong();
-      data.movingTime = source.readLong();
+      data.stopTime = source.readLong();
-      data.totalTime = source.readLong();
       data.totalDistance = source.readDouble();
-      data.totalElevationGain = source.readDouble();
+      data.totalTime = source.readLong();
-      data.maxSpeed = source.readDouble();
+      data.movingTime = source.readLong();
 
       double minLat = source.readDouble();
       double maxLat = source.readDouble();
@@ -570,9 +508,12 @@ public class TripStatistics implements Parcelable {
       double maxLong = source.readDouble();
       data.longitudeExtremities.set(minLong, maxLong);
 
+      data.maxSpeed = source.readDouble();
+
       double minElev = source.readDouble();
       double maxElev = source.readDouble();
       data.elevationExtremities.set(minElev, maxElev);
+      data.totalElevationGain = source.readDouble();
 
       double minGrade = source.readDouble();
       double maxGrade = source.readDouble();
@@ -600,18 +541,18 @@ public class TripStatistics implements Parcelable {
   @Override
   public void writeToParcel(Parcel dest, int flags) {
     dest.writeLong(startTime);
-    dest.writeLong(movingTime);
+    dest.writeLong(stopTime);
-    dest.writeLong(totalTime);
     dest.writeDouble(totalDistance);
-    dest.writeDouble(totalElevationGain);
+    dest.writeLong(totalTime);
-    dest.writeDouble(maxSpeed);
+    dest.writeLong(movingTime);
-
     dest.writeDouble(latitudeExtremities.getMin());
     dest.writeDouble(latitudeExtremities.getMax());
     dest.writeDouble(longitudeExtremities.getMin());
     dest.writeDouble(longitudeExtremities.getMax());
+    dest.writeDouble(maxSpeed);
     dest.writeDouble(elevationExtremities.getMin());
     dest.writeDouble(elevationExtremities.getMax());
+    dest.writeDouble(totalElevationGain);
     dest.writeDouble(gradeExtremities.getMin());
     dest.writeDouble(gradeExtremities.getMax());
   }

MyTracksTest/src/com/google/android/apps/mytracks/stats/TripStatisticsBuilderTest.java

@@ -25,55 +25,49 @@ public class TripStatisticsBuilderTest extends TestCase {
 
   public void testAddLocationSimple() throws Exception {
     builder = new TripStatisticsBuilder(1000);
-    TripStatistics stats = builder.getStatistics();
+    TripStatistics tripStatistics = builder.getTripStatistics();
 
     assertEquals(0.0, builder.getSmoothedElevation());
-    assertEquals(Double.POSITIVE_INFINITY, stats.getMinElevation());
+    assertEquals(Double.POSITIVE_INFINITY, tripStatistics.getMinElevation());
-    assertEquals(Double.NEGATIVE_INFINITY, stats.getMaxElevation());
+    assertEquals(Double.NEGATIVE_INFINITY, tripStatistics.getMaxElevation());
-    assertEquals(0.0, stats.getMaxSpeed());
+    assertEquals(0.0, tripStatistics.getMaxSpeed());
-    assertEquals(Double.POSITIVE_INFINITY, stats.getMinGrade());
+    assertEquals(Double.POSITIVE_INFINITY, tripStatistics.getMinGrade());
-    assertEquals(Double.NEGATIVE_INFINITY, stats.getMaxGrade());
+    assertEquals(Double.NEGATIVE_INFINITY, tripStatistics.getMaxGrade());
-    assertEquals(0.0, stats.getTotalElevationGain());
+    assertEquals(0.0, tripStatistics.getTotalElevationGain());
-    assertEquals(0, stats.getMovingTime());
+    assertEquals(0, tripStatistics.getMovingTime());
-    assertEquals(0.0, stats.getTotalDistance());
+    assertEquals(0.0, tripStatistics.getTotalDistance());
     for (int i = 0; i < 100; i++) {
-      Location l = new Location("test");
+      Location location = new Location("test");
-      l.setAccuracy(1.0f);
+      location.setAccuracy(1.0f);
-      l.setLongitude(45.0);
+      location.setLongitude(45.0);
 
-      // Going up by 5 meters each time.
+      // Going up by 1 meter each time.
-      l.setAltitude(i);
+      location.setAltitude(i);
-      // Moving by .1% of a degree latitude.
+      location.setLatitude(i * .001); // Moving by .001 degree latitude (111 meters)
-      l.setLatitude(i * .001);
+      location.setSpeed(11.1f);
-      l.setSpeed(11.1f);
       // Each time slice is 10 seconds.
       long time = 1000 + 10000 * i;
-      l.setTime(time);
+      location.setTime(time);
-      boolean moving = builder.addLocation(l, time);
+      boolean moving = builder.addLocation(location, time);
       assertEquals((i != 0), moving);
 
-      stats = builder.getStatistics();
+      tripStatistics = builder.getTripStatistics();
-      assertEquals(10000 * i, stats.getTotalTime());
+      assertEquals(10000 * i, tripStatistics.getTotalTime());
-      assertEquals(10000 * i, stats.getMovingTime());
+      assertEquals(10000 * i, tripStatistics.getMovingTime());
-      assertEquals(i, builder.getSmoothedElevation(),
+      assertEquals(i, builder.getSmoothedElevation(), Constants.ELEVATION_SMOOTHING_FACTOR / 2);
-                   Constants.ELEVATION_SMOOTHING_FACTOR / 2);
+      assertEquals(0.0, tripStatistics.getMinElevation());
-      assertEquals(0.0, stats.getMinElevation());
+      assertEquals(i, tripStatistics.getMaxElevation(), Constants.ELEVATION_SMOOTHING_FACTOR / 2);
-      assertEquals(i, stats.getMaxElevation(),
+      assertEquals(i, tripStatistics.getTotalElevationGain(), Constants.ELEVATION_SMOOTHING_FACTOR);
-                   Constants.ELEVATION_SMOOTHING_FACTOR / 2);
-      assertEquals(i, stats.getTotalElevationGain(),
-                   Constants.ELEVATION_SMOOTHING_FACTOR);
 
       if (i > Constants.SPEED_SMOOTHING_FACTOR) {
-        assertEquals(11.1f, stats.getMaxSpeed(), 0.1);
+        assertEquals(11.1f, tripStatistics.getMaxSpeed(), 0.1);
       }
-      if ((i > Constants.GRADE_SMOOTHING_FACTOR)
+      if (i > Constants.DISTANCE_SMOOTHING_FACTOR && i > Constants.ELEVATION_SMOOTHING_FACTOR) {
-          && (i > Constants.ELEVATION_SMOOTHING_FACTOR)) {
+        // 1 m / 111 m = .009
-        assertEquals(0.009, stats.getMinGrade(), 0.0001);
+        assertEquals(0.009, tripStatistics.getMinGrade(), 0.0001);
-        assertEquals(0.009, stats.getMaxGrade(), 0.0001);
+        assertEquals(0.009, tripStatistics.getMaxGrade(), 0.0001);
       }
-      // 1 degree = 111 km
+      assertEquals(111.0 * i, tripStatistics.getTotalDistance(), 100);
-      // 1 timeslice = 0.001 degree = 111 m
-      assertEquals(111.0 * i, stats.getTotalDistance(), 100);
     }
   }
 
@@ -86,7 +80,7 @@ public class TripStatisticsBuilderTest extends TestCase {
       for (int j = 0; j < 100; j++) {
         assertEquals(0.0, builder.updateElevation(elevation));
         assertEquals(elevation, builder.getSmoothedElevation());
-        TripStatistics data = builder.getStatistics();
+        TripStatistics data = builder.getTripStatistics();
         assertEquals(elevation, data.getMinElevation());
         assertEquals(elevation, data.getMaxElevation());
         assertEquals(0.0, data.getTotalElevationGain());
@@ -104,80 +98,71 @@ public class TripStatisticsBuilderTest extends TestCase {
       } else {
         expectedGain = 1.0;
       }
-      assertEquals(expectedGain,
+      assertEquals(expectedGain, builder.updateElevation(i));
-                   builder.updateElevation(i));
       assertEquals(i, builder.getSmoothedElevation(), 20);
-      TripStatistics data = builder.getStatistics();
+      TripStatistics data = builder.getTripStatistics();
       assertEquals(0.0, data.getMinElevation(), 0.0);
-      assertEquals(i, data.getMaxElevation(),
+      assertEquals(i, data.getMaxElevation(), Constants.ELEVATION_SMOOTHING_FACTOR);
-                   Constants.ELEVATION_SMOOTHING_FACTOR);
+      assertEquals(i, data.getTotalElevationGain(), Constants.ELEVATION_SMOOTHING_FACTOR);
-      assertEquals(i, data.getTotalElevationGain(),
-                   Constants.ELEVATION_SMOOTHING_FACTOR);
     }
   }
 
   public void testGradeSimple() throws Exception {
     for (double i = 0; i < 1000; i++) {
-      // The value of the elevation does not matter.  This is just to fill the
+      // The value of the elevation does not matter. This is just to fill the
       // buffer.
       builder.updateElevation(i);
       builder.updateGrade(100, 100);
-      if ((i > Constants.GRADE_SMOOTHING_FACTOR)
+      if ((i > Constants.GRADE_SMOOTHING_FACTOR) && (i > Constants.ELEVATION_SMOOTHING_FACTOR)) {
-          && (i > Constants.ELEVATION_SMOOTHING_FACTOR)) {
+        assertEquals(1.0, builder.getTripStatistics().getMaxGrade());
-        assertEquals(1.0, builder.getStatistics().getMaxGrade());
+        assertEquals(1.0, builder.getTripStatistics().getMinGrade());
-        assertEquals(1.0, builder.getStatistics().getMinGrade());
       }
     }
     for (double i = 0; i < 1000; i++) {
-      // The value of the elevation does not matter.  This is just to fill the
+      // The value of the elevation does not matter. This is just to fill the
       // buffer.
       builder.updateElevation(i);
       builder.updateGrade(100, -100);
-      if ((i > Constants.GRADE_SMOOTHING_FACTOR)
+      if ((i > Constants.GRADE_SMOOTHING_FACTOR) && (i > Constants.ELEVATION_SMOOTHING_FACTOR)) {
-          && (i > Constants.ELEVATION_SMOOTHING_FACTOR)) {
+        assertEquals(1.0, builder.getTripStatistics().getMaxGrade());
-        assertEquals(1.0, builder.getStatistics().getMaxGrade());
+        assertEquals(-1.0, builder.getTripStatistics().getMinGrade());
-        assertEquals(-1.0, builder.getStatistics().getMinGrade());
       }
     }
   }
 
   public void testGradeIgnoreShort() throws Exception {
     for (double i = 0; i < 100; i++) {
-      // The value of the elevation does not matter.  This is just to fill the
+      // The value of the elevation does not matter. This is just to fill the
       // buffer.
       builder.updateElevation(i);
       builder.updateGrade(1, 100);
-      assertEquals(Double.NEGATIVE_INFINITY, builder.getStatistics().getMaxGrade());
+      assertEquals(Double.NEGATIVE_INFINITY, builder.getTripStatistics().getMaxGrade());
-      assertEquals(Double.POSITIVE_INFINITY, builder.getStatistics().getMinGrade());
+      assertEquals(Double.POSITIVE_INFINITY, builder.getTripStatistics().getMinGrade());
     }
   }
 
   public void testUpdateSpeedIncludeZero() {
     for (int i = 0; i < 1000; i++) {
       builder.updateSpeed(i + 1000, 0.0, i, 4.0);
-      assertEquals(0.0, builder.getStatistics().getMaxSpeed());
+      assertEquals(0.0, builder.getTripStatistics().getMaxSpeed());
-      assertEquals((i + 1) * 1000, builder.getStatistics().getMovingTime());
     }
   }
 
   public void testUpdateSpeedIngoreErrorCode() {
     builder.updateSpeed(12345000, 128.0, 12344000, 0.0);
-    assertEquals(0.0, builder.getStatistics().getMaxSpeed());
+    assertEquals(0.0, builder.getTripStatistics().getMaxSpeed());
-    assertEquals(1000, builder.getStatistics().getMovingTime());
   }
 
   public void testUpdateSpeedIngoreLargeAcceleration() {
     builder.updateSpeed(12345000, 100.0, 12344000, 1.0);
-    assertEquals(0.0, builder.getStatistics().getMaxSpeed());
+    assertEquals(0.0, builder.getTripStatistics().getMaxSpeed());
-    assertEquals(1000, builder.getStatistics().getMovingTime());
   }
 
   public void testUpdateSpeed() {
     for (int i = 0; i < 1000; i++) {
       builder.updateSpeed(i + 1000, 4.0, i, 4.0);
-      assertEquals((i + 1) * 1000, builder.getStatistics().getMovingTime());
       if (i > Constants.SPEED_SMOOTHING_FACTOR) {
-        assertEquals(4.0, builder.getStatistics().getMaxSpeed());
+        assertEquals(4.0, builder.getTripStatistics().getMaxSpeed());
       }
     }
   }