1.根据经纬度 查询附近信息
/** *计算某个经纬度的周围某段距离的正方形的四个点 * *@param lng float 经度 *@param lat float 纬度 *@param distance float 该点所在圆的半径,该圆与此正方形内切,默认值为0.5千米 *@return array 正方形的四个点的经纬度坐标 */ function returnSquarePoint($lng, $lat, $distance){ $distance = $distance?$distance:5; $earthRadius = 6378; $dlng = 2 * asin(sin($distance / (2 * $earthRadius)) / cos(deg2rad($lat))); $dlng = rad2deg($dlng); $dlat = $distance/$earthRadius; $dlat = rad2deg($dlat); return array( 'left-top'=>array('lat'=>$lat + $dlat,'lng'=>$lng-$dlng), 'right-top'=>array('lat'=>$lat + $dlat, 'lng'=>$lng + $dlng), 'left-bottom'=>array('lat'=>$lat - $dlat, 'lng'=>$lng - $dlng), 'right-bottom'=>array('lat'=>$lat - $dlat, 'lng'=>$lng + $dlng) ); } $info_sql = "select id,locateinfo,lat,lng from `lbs_info` where lat<>0 and lat>{$squares['right-bottom']['lat']} and lat{$squares['left-top']['lng']} and lng<{$squares['right-bottom']['lng']} ";
2.计算两点之间的距离
/** * @desc 根据两点间的经纬度计算距离 * @param float $lat 纬度值 * @param float $lng 经度值 */ private function getDistance($lat1, $lng1, $lat2, $lng2){ $earthRadius = 6367; //approximate radius of earth in meters $lat1 = ($lat1 * pi() ) / 180; $lng1 = ($lng1 * pi() ) / 180; $lat2 = ($lat2 * pi() ) / 180; $lng2 = ($lng2 * pi() ) / 180; $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,2); }