How can i calculate the distance between two gps points in Java?

Question

I used this code but it doesnt work:

Need the distance between two gps coordinates like 41.1212, 11.2323 in kilometers (Java)

double d2r = (180 / Math.PI); double distance = 0;  try{     double dlong = (endpoint.getLon() - startpoint.getLon()) * d2r;     double dlat = (endpoint.getLat() - startpoint.getLat()) * d2r;     double a =         Math.pow(Math.sin(dlat / 2.0), 2)             + Math.cos(startpoint.getLat() * d2r)             * Math.cos(endpoint.getLat() * d2r)             * Math.pow(Math.sin(dlong / 2.0), 2);     double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));     double d = 6367 * c;      return d;  } catch(Exception e){     e.printStackTrace(); } 

Answer 1

Longitude and latitude are given in degrees (0-360). If you want to convert degrees to radians (0-2π) you need to divide by 360 and multiply by 2π, (or equivalently, multiply by π/180). In your code however, you multiply by 180/π.

That is, change

double d2r = (180 / Math.PI); 

into

double d2r = Math.PI / 180; 

Answer 2

have a look a Geocalc

Coordinate lat = new GPSCoordinate(41, .1212); Coordinate lng = new GPSCoordinate(11, .2323); Point point = new Point(lat, lng);  lat = new DegreeCoordinate(51.4613418); lng = new DegreeCoordinate(-0.3035466); Point point2 = new Point(lat, lng); System.out.println("Distance is " + EarthCalc.getDistance(point2, point) / 1000 + " km"); 

Distance is 1448.7325760822912 km

I wrote that library for one my project.