定义π
define('PI',3.1415926535898);
define('EARTH_RADIUS',6378.137);
计算两组经纬度坐标 之间的距离
/**
* 计算两组经纬度坐标 之间的距离
* params :lat1 纬度1; lng1 经度1; lat2 纬度2; lng2 经度2; len_type (1:m or 2:km);
* return m or km
*/
function GetDistance($lat1, $lng1, $lat2, $lng2, $len_type = 1, $decimal = 2) {
$radLat1 = $lat1 * PI / 180.0;
$radLat2 = $lat2 * PI / 180.0;
$a = $radLat1 - $radLat2;
$b = ($lng1 * PI / 180.0) - ($lng2 * PI / 180.0);
$s = 2 * asin(sqrt(pow(sin($a/2),2) + cos($radLat1) * cos($radLat2) * pow(sin($b/2),2)));
$s = $s * EARTH_RADIUS;
$s = round($s * 1000);
if ($len_type > 1){
$s /= 1000;
}
return round($s, $decimal);
}
获取两个坐标之间的距离
$a = GetDistance(20.035556,110.33269,20.046521,110.343057);
echo $a;