php - sort a multidimensional array using array_multisort

Question

I have this array

Array
(
    [0] => Array
        (
            [brand] => blah blah
            [location] => blah blah
            [address] => blah blah
            [city] => blah blah
            [state] => CA
            [zip] => 90210
            [country] => USA
            [phone] => 555-1212
            [long] => -111
            [lat] => 34
            [distance] => 3.08
        )
    [1] => Array
        (
            [brand] => blah blah
            [location] => blah blah
            [address] => blah blah
            [city] => blah blah
            [state] => CA
            [zip] => 90210
            [country] => USA
            [phone] => 555-1212
            [long] => -111
            [lat] => 34
            [distance] => 5
        )
.
.
.

}

I want to be able to sort the arrays in the hash by distance.

Answer 1

You need to extract all the distances first, then pass both the distance and the data to the function. As shown in example 3 in the array_multisort documentation.

foreach ($data as $key => $row) {
    $distance[$key] = $row['distance'];
}

array_multisort($distance, SORT_ASC, $data);

This assumes you want the shortest distances first, otherwise change the SORT_ASC to SORT_DESC