Center coordinate of a set of CLLocationsCoordinate2D
Hmm... it depends how you define the centre of the points. Does it depend on the distribution etc...
An easy way to do it is as follows...
//find rect that encloses all coords
float maxLat = -200;
float maxLong = -200;
float minLat = MAXFLOAT;
float minLong = MAXFLOAT;
for (int i=0 ; i<[locations count] ; i++) {
CLLocationCoordinate2D location = [locations objectAtIndex:i];
if (location.latitude < minLat) {
minLat = location.latitude;
}
if (location.longitude < minLong) {
minLong = location.longitude;
}
if (location.latitude > maxLat) {
maxLat = location.latitude;
}
if (location.longitude > maxLong) {
maxLong = location.longitude;
}
}
//Center point
CLLocationCoordinate2D center = CLLocationCoordinate2DMake((maxLat + minLat) * 0.5, (maxLong + minLong) * 0.5);
This will give the center of the rect covering all the points. However it does not take the spread into account.
i.e.
. = point
X = centre
..... X .
EDIT
Corrected some of the maths.
I know it's really late but someone could read this and help himself Using Fogmeister answer you could create a MKCoordinateRegion
CLLocationDegrees minLat,minLng,maxLat,maxLng;
for(CLLocationCoordinate2D coordinate in coordinates) {
minLat = MIN(minLat, coordinate.latitude);
minLng = MIN(minLng, coordinate.longitude);
maxLat = MAX(maxLat, coordinate.latitude);
maxLng = MAX(maxLng, coordinate.longitude);
}
CLLocationCoordinate2D coordinateOrigin = CLLocationCoordinate2DMake(minLat, minLng);
CLLocationCoordinate2D coordinateMax = CLLocationCoordinate2DMake(maxLat, maxLng);
MKMapPoint upperLeft = MKMapPointForCoordinate(coordinateOrigin);
MKMapPoint lowerRight = MKMapPointForCoordinate(coordinateMax);
//Create the map rect
MKMapRect mapRect = MKMapRectMake(upperLeft.x,
upperLeft.y,
lowerRight.x - upperLeft.x,
lowerRight.y - upperLeft.y);
//Create the region
MKCoordinateRegion region = MKCoordinateRegionForMapRect(mapRect);
//THIS HAS THE CENTER, it should include spread
CLLocationCoordinate2D centerCoordinate = region.center;
Greetings!!!
You can also get both the center
of an array of CLLocationCoordinate2D
s and a span
.
extension MKCoordinateRegion {
init(coordinates: [CLLocationCoordinate2D]) {
var minLatitude: CLLocationDegrees = 90.0
var maxLatitude: CLLocationDegrees = -90.0
var minLongitude: CLLocationDegrees = 180.0
var maxLongitude: CLLocationDegrees = -180.0
for coordinate in coordinates {
let lat = Double(coordinate.latitude)
let long = Double(coordinate.longitude)
if lat < minLatitude {
minLatitude = lat
}
if long < minLongitude {
minLongitude = long
}
if lat > maxLatitude {
maxLatitude = lat
}
if long > maxLongitude {
maxLongitude = long
}
}
let span = MKCoordinateSpanMake(maxLatitude - minLatitude, maxLongitude - minLongitude)
let center = CLLocationCoordinate2DMake((maxLatitude - span.latitudeDelta / 2), (maxLongitude - span.longitudeDelta / 2))
self.init(center: center, span: span)
}
}
Usage:
let region = MKCoordinateRegion(coordinates: coordinates)
region.center
region.span