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[zword]

I'm still trying to figure out how to calculate the current speed of my application. From my point of view the calculation should be correct but now I only get values of 0.0 or slightly above.
I tried it with my car when I drove about 50km/h. I would be very grateful if somebody could help me.

Here is my code:

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
		
		NSLog(@"Updating location");
		
		NSDate *newLocationEventDate = newLocation.timestamp;
		//no pointer because it is a C-Class
		NSTimeInterval howRecentNewLocation = [newLocationEventDate timeIntervalSinceNow];
	
	//initial Update, no oldLocation available therefore it won't be checked how good the data is 
	if(firstUpdate) {
		
		if (signbit(newLocation.horizontalAccuracy)) {
			// Negative accuracy means an invalid or unavailable measurement
			NSLog(@"LatLongUnavailable");
			UIAlertView *myAlert = [[UIAlertView alloc] initWithTitle:@"Error Alert" message:@"LatLongUnavailable" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"exit", nil];
			[myAlert show];
			[myAlert release];
		}
		else{
			myLocation = [newLocation retain];
			[self updatedGPS:newLocation];
			firstUpdate = NO;
			[mySpinner stopAnimating];
			isUpdating = NO; 
			return;
		}
	}
		
	if(isUpdating){
		if (signbit(newLocation.horizontalAccuracy)) {
			// Negative accuracy means an invalid or unavailable measurement
			NSLog(@"LatLongUnavailable");
			UIAlertView *myAlert = [[UIAlertView alloc] initWithTitle:@"Error Alert" message:@"LatLongUnavailable" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"exit", nil];
			[myAlert show];
			[myAlert release];
		}
		else{
			timesFired++;
			//filter cached and too old locations
			//1.Version:
			//if((myLocation.horizontalAccuracy > newLocation.horizontalAccuracy) && (howRecentNewLocation < -0.0 && howRecentNewLocation > -10.0)) {
			//2.Version
			if(howRecentNewLocation < -0.0 && howRecentNewLocation > -10.0){
				//release the cached location, if available
				if(myLocation)
					[myLocation release];
				myLocation =[newLocation retain];
			}
			
				[self updatedGPS:myLocation];
				timesFired = 0;
				[mySpinner stopAnimating];
				return;
			}
		}
	}
}
  

- (void)updatedGPS:(CLLocation *)goodLocation{
	
	//methode variables for calculating the current and avg speed
	CLLocationDistance distanceMoved;
	NSTimeInterval timeElapsed;
	
	
	NSLog(@"uptadedGPS entered:");
	NSLog(@"Lat: %f", goodLocation.coordinate.latitude);
	NSLog(@"Long: %f", goodLocation.coordinate.longitude);
	
	//calculate distance moved and time elapsed, but only if we have an "old" location
	if(oldLocation != nil) {
		distanceMoved = [goodLocation getDistanceFrom:oldLocation];
		timeElapsed = [goodLocation.timestamp timeIntervalSinceDate:oldLocation.timestamp];
	}
	else{
		distanceMoved = 0.0;
		timeElapsed = 1.0;
	}
	
	//formatting to km/h
	currentSpeed = (distanceMoved*0.001)/(timeElapsed*360);
	currentSpeedLabel.text = [NSString stringWithFormat:@"%3.1f", currentSpeed];
	NSLog(@"currentSpeed: %f", currentSpeed);
	}
	//save the latest goodLocation for calculating the speed
	oldLocation = [goodLocation retain];
	
	
}