待续：经纬短算距离

参考：

http://forum.webhelp.pl/php-i-bazy-danych/odleglosc-miedzy-dwoma-punktami-t234347.html

http://forum.php.pl/lofiversion/index.php/t142890.html

rad2deg(acos(sin(deg2rad($sz1)) * sin(deg2rad($row['sz']) + cos(deg2rad($sz1)) * cos(deg2rad($row['sz'])) * cos(deg2rad($wy1-$row['wy'])))) * 111.18957696

或者

$dystans = round (rad2deg(acos(sin(deg2rad($szgeo1)) * sin(deg2rad($szgeo2)) +  cos(deg2rad($szgeo1)) * cos(deg2rad($szgeo2)) * cos(deg2rad($dlgeo1 - $dlgeo2))))  * 111.18957696);