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iOS

Posted by Tom Coomer
Tom Coomer
1,331 Points

How to calculate distance between two longitude and latitude points.

How do I calculate the distance between two longitude and latitude points in Swift.

I have the users current location and need to work out the distance between another location.

Thanks

Andres Oliva
Andres Oliva
7,810 Points

I'm just commenting because I want to know how too :P

3 Answers

James Barnett
James Barnett
39,199 Points
James Barnett
James Barnett
39,199 Points

The easiest way to do this is to use the Haversine Formula

Here's some code to get you started 

+ (CGFloat)directMetersFromCoordinate:(CLLocationCoordinate2D)from toCoordinate:(CLLocationCoordinate2D)to {

    static const double DEG_TO_RAD = 0.017453292519943295769236907684886;  
    static const double EARTH_RADIUS_IN_METERS = 6372797.560856;  

    double latitudeArc  = (from.latitude - to.latitude) * DEG_TO_RAD;
    double longitudeArc = (from.longitude - to.longitude) * DEG_TO_RAD;
    double latitudeH = sin(latitudeArc * 0.5);
    latitudeH *= latitudeH;
    double lontitudeH = sin(longitudeArc * 0.5);
    lontitudeH *= lontitudeH;
    double tmp = cos(from.latitude*DEG_TO_RAD) * cos(to.latitude*DEG_TO_RAD);
    return EARTH_RADIUS_IN_METERS * 2.0 * asin(sqrt(latitudeH + tmp*lontitudeH));
}

from: http://www.codecodex.com/wiki/Calculate_Distance_Between_Two_Points_on_a_Globe#Objective_C

notf0und
notf0und
11,940 Points
notf0und
notf0und
11,940 Points

This website details lots of different methods in JavaScript, but it's the equations you'll want: http://www.movable-type.co.uk/scripts/latlong.html

Good luck! Hope this helps.

James Barnett
James Barnett
39,199 Points
James Barnett
James Barnett
39,199 Points

You might also check out

https://stackoverflow.com/questions/3109084/calculate-distance-between-two-place-using-latitude-longitude-in-gmap-for-iphone?rq=1