How to sort an array of array elements based on values in another array in PHP 5.3?

Question

I have an array which holds around 5000 array elements, each in the following format:

Array
        (
            [keywordid] => 98
            [keyword] => sample keyword 34
            [type] => NATURAL
            [longname] => UK
        )

I have a second array which holds numerical values such as the following:

Array
(
    [0] => 55
    [1] => 56
    [2] => 57
    [3] => 58
    [4] => 59
    [5] => 1065
    [6] => 1066
    [7] => 1067
    [8] => 1083
)

Each value in the array above corresponds to the 'keywordid' value within each array of the first array. I want to sort the first array, so that those arrays whose keywordid has a value matching an element in the second array, appear first and the rest of the arrays appear afterwards in no specified order. How do I accomplish this? I am using PHP 5.3, backwards compatibility is not a requirement.

Appreciate the help.

Answer 1

I would probably use usort

usort($array1, function($a, $b) use($array2) {
    $k1 = array_search($a['keywordid'], $array2);
    $k2 = array_search($b['keywordid'], $array2);

    if ($k1 == $k2) {
        return 0;
    }
    return ($k1 < $k2) ? -1 : 1;
});

There is probably a better way but that came to mind first.

Answer 2

try this code to manipulate that array:

<?php
//here I assume you have more than one array
$array = array (
            0=> array (
            "keywordid" => 98,
            "keyword" => "sample keyword 34",
            "type" => "NATURAL",
            "longname" => "UK"),
            1=> array (
            "keywordid" => 95,
            "keyword" => "sample keyword 95",
            "type" => "NATURAL 02",
            "longname" => "US"),
            2=> array (
            "keywordid" => 55,
            "keyword" => "sample keyword 55",
            "type" => "NATURAL 02",
            "longname" => "AU")

        );

//populate array into new variable
foreach ( $array  as $key=> $val){
    $out[] = $val["keywordid"];
}

echo "<pre>";
print_r($out);
echo "</pre>";  

?>

the Output is:

Array
(
    [0] => 98
    [1] => 95
    [2] => 55
)