chunk array vertically

$arr    = range(1, 19);
function array_chunk_vertical($arr, $percolnum){
    $n = count($arr);
    $mod    = $n % $percolnum;
    $cols   = floor($n / $percolnum);
    $mod ? $cols++ : null ;
    $re     = array();
    for($col = 0; $col < $cols; $col++){
        for($row = 0; $row < $percolnum; $row++){
            if($arr){
                $re[$row][]   = array_shift($arr);
            }
        }
    }
    return $re;
}
$result = array_chunk_vertical($arr, 6);
foreach($result  as $row){
    foreach($row as $val){
        echo '['.$val.']';
    }
    echo '<br/>';
}
/*
[1][7][13][19]
[2][8][14]
[3][9][15]
[4][10][16]
[5][11][17]
[6][12][18]
 */