php converting number

Question

Let's say I have numbers like

123456000000
12345000000
123456000
123456

and I want them to show up as

123.45B
12.345B
123.45M
123,456

The best way I can think of to do this is by getting string length to determine if I need a B, M, or nothing but commas and just substr the first five chars. I'm sure there is a better way though and I don't want to get too far before I realize that my idea sucks. hah.

Any good recommendations?

EDIT

My apologies on the confusion of the B and M. Those represent:

• B illion
• M illion

Answer 1

Okay, so my previous answer considered you were dealing with file sizes, and I deleted it. However the logic of this solution is the same:

function format_number($num) {
     if($num < 1000000) {
        return number_format($num);
     } elseif ($num < 1000000000) {
        return number_format($num/1000000, 2) . 'M';
     } else {
        return number_format($num/1000000000, 2) . 'B';
     }
}

http://codepad.org/nb89ze5J

Answer 2

Don't know about the last B or M part but there is a function called number_format in PHP which does the following (from the documentation) -

$number = 1234.56;

// english notation (default)
$english_format_number = number_format($number);
// 1,235

// French notation
$nombre_format_francais = number_format($number, 2, ',', ' ');
// 1 234,56

$number = 1234.5678;

// english notation without thousands separator
$english_format_number = number_format($number, 2, '.', '');
// 1234.57