PHP 二维数组排序 方便~~
array_multisort() 对二维数组进行排序http://www.ucantech.net/网站推广
数组$roughData，我们打算按照accurancy排序。

Array
(
    [0] => Array
        (
            [username] => 10yl
            [accuracy] => 0.00
        )

    [1] => Array
        (
            [username] => 11yl
            [accuracy] => 1.00
        )

    [2] => Array
        (
            [username] => 12yl
            [accuracy] => 0.00
        )

    [3] => Array
        (
            [username] => 13yl
            [accuracy] => 1.00
        )
)

方法：
（1）提取accuracy列数组

foreach ($roughData as $key => $row) {
            $usernames[$key] = $row['username'];
            $accuracy[$key] = $row['accuracy'];
}

（2）进行排序

array_multisort($accuracy, SORT_ASC,$roughData);

当print_r($roughData);后我们将得到一个按accuracy升序排序的二维数组(fblww-1230)