public class GeoLocation
{
    public static final double RADIUS = 3963.1676;

    public static final double KM_PER_MILE = 1.60934;

    private double latitude;
    private double longitude;

    public GeoLocation(double theLatitude, double theLongitude)
    {
        latitude = theLatitude;
        longitude = theLongitude;
    }
    public double getLatitude()
    {
        return latitude;
    }
    public double getLongitude()
    {
        return longitude;
    }
    public String toString()
    {
        return "latitude: " + latitude + ", longitude: " + longitude;
    }
    public double distanceFrom(GeoLocation other)
    {
        double lat1 = Math.toRadians(latitude);
        double long1 = Math.toRadians(longitude);
        double lat2 = Math.toRadians(other.latitude);
        double long2 = Math.toRadians(other.longitude);
        double theCos = Math.sin(lat1) * Math.sin(lat2) +
            Math.cos(lat1) * Math.cos(lat2) * Math.cos(long1 - long2);
        double arcLength = Math.acos(theCos);
        double result = arcLength * RADIUS;
        return result;
    }
    public double distanceFromInKilometers(GeoLocation other)
    {
        double lat1 = Math.toRadians(latitude);
        double long1 = Math.toRadians(longitude);
        double lat2 = Math.toRadians(other.latitude);
        double long2 = Math.toRadians(other.longitude);
        double theCos = Math.sin(lat1) * Math.sin(lat2) +
            Math.cos(lat1) * Math.cos(lat2) * Math.cos(long1 - long2);
        double arcLength = Math.acos(theCos);
        double result = arcLength * RADIUS;
        double result2 = result * KM_PER_MILE;
        return result2;
    }
}