php版
function rad($d)
{
return $d * 3.1415926535898 / 180.0;
}
function GetDistance($lat1, $lng1, $lat2, $lng2)
{
$EARTH_RADIUS = 6378.137; //公里
$radLat1 = rad($lat1);
$radLat2 = rad($lat2);
$a = $radLat1 – $radLat2;
$b = rad($lng1) – rad($lng2);
$s = 2 * asin(sqrt(pow(sin($a/2),2) +
cos($radLat1)*cos($radLat2)*pow(sin($b/2),2)));
$s = $s *$EARTH_RADIUS;
$s = round($s * 10000) / 10000;
return $s;
}
mysql版
CREATE DEFINER=`root`@`localhost` FUNCTION `distance`(lat1 float,lng1 float,lat2 float,lng2 float) RETURNS float
BEGIN
set @num=
2 * 6378.137* ASIN(SQRT(POW(SIN(PI() * (lat1 – lat2) / 360), 2) + COS(PI() * lat1 / 180)
* COS(lat2* PI() / 180) * POW(SIN(PI() * (lng1 – lng2) / 360), 2)));
RETURN @num;
END