将4位数整数转换为十进制数

Question

I am trying to convert a 4 digit integer like 1999 to 19.99.

I have looked at functions like money_format() but this seems to not be what I am looking for. Here is a function I wrote but there must be pre-existing method to do this?

function numberToDecimal((int)$num) {
    if(!preg_match('/^\d{4}$/', $num) return;
    $parsed = (string)$num;
    $i      = 0;
    $ret    = $parsed[$i++] . $parsed[$i++] . '.';
    $ret   .= $parsed[$i++] . $parsed[$i];
    return $ret;
}

Thank-you in advance.
See the code working over at corresponding to the answer 3v4l.

Answer 1

What about the following:

$money = 1999 ;
echo number_format(($money /100), 2, '.', ' ');
// Will output: 19.99