Distance

distance

public static function distance($lat1, $lon1, $lat2, $lon2)
        {
                $theta = $lon1 - $lon2;
                $dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) +  cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta));
                $dist = acos($dist);
                $dist = rad2deg($dist);
                $kilometers = $dist * 60 * 1.8531596160;
                return $kilometers;
        }