/*** @desc 根据两点间的经纬度计算距离* @param float $lat 纬度值* @param float $lng 经度值*/ function getDistance($lat1, $lng1, $lat2, $lng2) { $earthRadius = 6367000; //approximate radius of earth in meters /* Convert these degrees to radians to work with the formula */ $lat1 = ($lat1 * pi() ) / 180; $lng1 = ($lng1 * pi() ) / 180; $lat2 = ($lat2 * pi() ) / 180; $lng2 = ($lng2 * pi() ) / 180; /* Using the Haversine formula http://en.wikipedia.org/wiki/Haversine_formula calculate the distance */ $calcLongitude = $lng2 - $lng1; $calcLatitude = $lat2 - $lat1; $stepOne = pow(sin($calcLatitude / 2), 2) + cos($lat1) * cos($lat2) * pow(sin($calcLongitude / 2), 2); $stepTwo = 2 * asin(min(1, sqrt($stepOne))); $calculatedDistance = $earthRadius * $stepTwo; return round($calculatedDistance); }附一个在线计算两点距离的地址：
http://www.nhc.noaa.gov/gccalc.shtml
注：原文链接：http://my.oschina.net/ekc/blog/84106
原文：http://www.cnblogs.com/amw863/p/4488596.html