<!-- Collection of code snippets by Arne Vajhøj -->
<!-- posted to eksperten.dk, usenet and other places (2002-now) -->
<?php
function anyradix($num, $radixstr) {
        $radix = strlen($radixstr);
        $tmp = $num;
        $res = '';
        while($tmp > 0) {
                $dig = $tmp % $radix;
                $tmp = (int)($tmp / $radix);
                $res = $radixstr[$dig] . $res;
        }
        return $res;
}

echo anyradix(254, '01234567') . "\r\n";
echo anyradix(254, '0123456789') . "\r\n";
echo anyradix(254, '0123456789ABCDEF') . "\r\n";
echo anyradix(254, '0123456789abcdef') . "\r\n";
echo anyradix(254, '0123456789ABCDEFabcdef') . "\r\n";
echo anyradix(257, '01234567') . "\r\n";
echo anyradix(257, '0123456789') . "\r\n";
echo anyradix(257, '0123456789ABCDEF') . "\r\n";
echo anyradix(257, '0123456789abcdef') . "\r\n";
echo anyradix(257, '0123456789ABCDEFabcdef') . "\r\n";
?>