How to Remove Bad GPS Coordinate

问题

As shown in the image below, there is a sudden jump in GPS coordinate while I keep track of user activity (walking, biking or driving).

I do not know how to fix this problem even though I have already attempted multiple ways to solve, but as a reference I also posted my code below.

In this image screenshot, I parked my car and walked to campus and came to my office, but it shows me that I went to Harvest Ln which is not right.

   -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations{



    iNEAT_o_GamesAppDelegate *appDelegate = (iNEAT_o_GamesAppDelegate *)[[UIApplication sharedApplication] delegate];

    CoordinateModel *coord = [[CoordinateModel alloc] init];

    ActivityType currentActivityType = [DataManager sharedInstance].activityType;

    for(int i=0;i<locations.count;i++){
        CLLocation * newLocation = [locations objectAtIndex:i];
        CLLocationCoordinate2D theLocation = newLocation.coordinate;
        CLLocationAccuracy theAccuracy = newLocation.horizontalAccuracy;
        NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow];

        if (locationAge > 30.0)
            continue;

        //Select only valid location and also location with good accuracy
        if(newLocation!=nil&&theAccuracy>0
           &&theAccuracy<2000
           &&(!(theLocation.latitude==0.0&&theLocation.longitude==0.0))){
            coord.latitude = theLocation.latitude;
            coord.longitude = theLocation.longitude;

                   if (currentActivityType == 0) {
                        // walking
                        [appDelegate.walkingCoordinates addObject:coord];
                    }
                    else if(currentActivityType == 1) {
                        [appDelegate.bikingCoordinates addObject:coord];
                    }
                    else if(currentActivityType == 2) {
                        // driving
                        [appDelegate.drivingCoordinates addObject:coord];
                    }
        }
    }
}

回答1:

I have added another condition for walking activity and limited only accuracy between 0-60 meters. and work perfectly fine. Thanks Allessandro and Skladek feedback above.

 -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations{




    iNEAT_o_GamesAppDelegate *appDelegate = (iNEAT_o_GamesAppDelegate *)[[UIApplication sharedApplication] delegate];

    CoordinateModel *coord = [[CoordinateModel alloc] init];

    ActivityType currentActivityType = [DataManager sharedInstance].activityType;

    for(int i=0;i<locations.count;i++){
        CLLocation * newLocation = [locations objectAtIndex:i];
        CLLocationCoordinate2D theLocation = newLocation.coordinate;
        CLLocationAccuracy theAccuracy = newLocation.horizontalAccuracy;
        NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow];

        if (locationAge > 30.0)
            continue;

        //Select only valid location and also location with good accuracy
        if(newLocation!=nil&&theAccuracy>0
           &&theAccuracy<2000
           &&(!(theLocation.latitude==0.0&&theLocation.longitude==0.0))){
            coord.latitude = theLocation.latitude;
            coord.longitude = theLocation.longitude;

                   if (currentActivityType == 0 && theAccuracy<60) {
                        // walking
                        [appDelegate.walkingCoordinates addObject:coord];
                    }
                    else if(currentActivityType == 1) {
                        [appDelegate.bikingCoordinates addObject:coord];
                    }
                    else if(currentActivityType == 2) {
                        // driving
                        [appDelegate.drivingCoordinates addObject:coord];
                    }
        }
    }
}

来源：https://stackoverflow.com/questions/23833758/how-to-remove-bad-gps-coordinate