if(!function_exists('to_alphabet')){
function to_alphabet($index){
$str = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$length = strlen($str);
$base = floor($index / $length);
$remain = $index % $length;
$c1 = '';
$c2 = '';
if($base > 0){
$index = $base - 1;
$c1 = substr($str, $index, 1);
}
$index = $remain;
$c2 = substr($str, $index, 1);
$c = $c1 . $c2;
//logg($c);
return $c;
}
}
e.g.
- 0 -> A
- 25 -> Z
- 26 -> AA
- 29 -> AD