Android经纬度转化为距离

/**
 * 
 *         经纬度转化为距离
 * 
 */
public class Distance {


public static double GetDistance(double p1Lat, double p1Lng, double p2Lat,
double p2Lng) {
double dLat1InRad = p1Lat * (Math.PI / 180);
double dLong1InRad = p1Lng * (Math.PI / 180);
double dLat2InRad = p2Lat * (Math.PI / 180);
double dLong2InRad = p2Lng * (Math.PI / 180);
double dLongitude = dLong2InRad - dLong1InRad;
double dLatitude = dLat2InRad - dLat1InRad;
double a = Math.pow(Math.sin(dLatitude / 2), 2) + Math.cos(dLat1InRad)
* Math.cos(dLat2InRad) * Math.pow(Math.sin(dLongitude / 2), 2);
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
double dDistance = EarthRadiusKm * c;
return dDistance;
}


public static double EarthRadiusKm = 6378.137; // WGS-84
}