compare 2 php arrays and duplicate or reduce the values of the second so they match

php-compare-fill-array.php

// only if the two arrays don't hold the same number of elements
if (count($data) != count($colors)) {
    // handle if $colors is less than $data
    while (count($colors) < count($data)) {
        // NOTE : we are using array_values($colors) to make sure we use
        //        numeric keys.
        //        See http://php.net/manual/en/function.array-merge.php)
        $colors = array_merge($colors, array_values($colors));
    }

    // handle if $colors has more than $data
    $colors = array_slice($colors, 0, count($data));
}