Sort a multidimensional array by a column

Question

My array $servers looks like this

Array
(
    [0] => Array
        (
            [0] => Dell PowerEdge R210 II
            [1] => 8
            [2] => Array()
        )

    [1] => Array
        (
            [0] => Dell PowerEdge R210 II 2
            [1] => 2
            [2] => Array()
        )

    [2] => Array
        (
            [0] => Dell PowerEdge R210 II 3
            [1] => 3
            [2] => Array()
        )

    [3] => Array
        (
            [0] => Dell PowerEdge R210 II 4
            [1] => 4
            [2] => Array()
        )

    [4] => Array
        (
            [0] => Dell PowerEdge R210 II 5
            [1] => 5
            [2] => Array()
        )

    [5] => Array
        (
            [0] => Dell PowerEdge R210 II 6
            [1] => 6
            [2] => Array()
        )
)

I'd like to have the array re-arranged and put back into $servers but in order of $servers[x][1]

So where the singular number is (1st object is 8) I'd like it to sort it with the smallest number 1st, moving to the largest!

ps I tried this

<?php
function cmp($a, $b)
{
    if ($a == $b) {
        return 0;
    }
    return ($a < $b) ? -1 : 1;
}

$a = array(3, 2, 5, 6, 1);

usort($servers, "cmp");
?>

but it didnt seem to work!

Answer 1

Your cmp is wrong. $a and $b are arrays like

Array
    (
        [0] => Dell PowerEdge R210 II 6
        [1] => 6
        [2] => Array
            (
                [0] => 6
                [1] => Sock
                [2] => Price
                [3] => ImageURL
                [4] => CPU
                [5] => Memory
                [6] => HDD
                [7] => Bandwidth
                [8] => OS
                [9] => Upgrades
                [10] => OrderLink
            )

    )

and you must compare $a[1] with $b[1]:

function cmp($a, $b) {
    return $a[1] - $b[1];
}