php查找附近的人

[php]代码库

	$uid=$_POST[uid];
	if($uid>0)
	{
		$re=mysql_query("select `lat`,`long` from pre_common_member where uid='$uid'")or die(mysql_error());
		$row=mysql_fetch_assoc($re);
		if(!empty($row[lat]) and !empty($row[long]))
		{
			$re0=mysql_query("select `username`,`lat`,`long` from pre_common_member where uid!='$uid'");
			while($row0=mysql_fetch_assoc($re0))
			{
				$distance = getDistanceBetweenPointsNew($row['lat'], $row['long'], $row0['lat'], $row0['long']);
				$row0[meter]=$distance[meters];
				$arr[]=$row0;
			}
			$arr=array_sort($arr,'meter');
			$arr = array_slice($arr,0,10); 
			$data=json_encode($arr);
			$s=mysql_errno();
			//echo $data;
			echo "{\"s\":$s,\"data\":$data}";
		}	
	}

// 比较两个地点的距离
function getDistanceBetweenPointsNew($latitude1, $longitude1, $latitude2, $longitude2)
{
    $theta = $longitude1 - $longitude2;
    $miles = (sin(deg2rad($latitude1)) * sin(deg2rad($latitude2))) + (cos(deg2rad($latitude1)) * cos(deg2rad($latitude2)) * cos(deg2rad($theta)));
    $miles = acos($miles);
    $miles = rad2deg($miles);
    $miles = $miles * 60 * 1.1515;
    $feet = $miles * 5280;
    $yards = $feet / 3;
    $kilometers = $miles * 1.609344;
    $meters = $kilometers * 1000;
    return compact('miles', 'feet', 'yards', 'kilometers', 'meters');
}
// 二维数组按某个key排序
function array_sort($arr,$keys,$type='asc')
{ 
	$keysvalue = $new_array = array();
	foreach ($arr as $k=>$v){
	$keysvalue[$k] = $v[$keys];
	}
	if($type == 'asc'){
	asort($keysvalue);
	}else{
	arsort($keysvalue);
	}
	reset($keysvalue);
	foreach ($keysvalue as $k=>$v){
	$new_array[$k] = $arr[$k];
	}
	return $new_array; 
}