5000 - 4999.99 = 0.0100000000002 ???

Anon

5000 - 4999.99 = 0.0100000000002

Can anyone think of a reason why I would be getting this stupid number?

The fields in the MySQL database are of type 'decimal(10,2)'.

The relevant code is this:

//$line is the variable used in the loop to store the rows

$fullactual = $line["AB_Actual"] + $line["AB_On_Order"];

$difference = $line["AB_Budget"] - $fullactual;

number_format($fullactual, 2);
number_format($difference, 2);

Firstly, what is wrong with this setup? It works fine for the vast majority of records, only a couple do this...

Secondly, is this the best way to handle working with currency/money in PHP/MySQL?

Thanks.

Anon

Nothing is wrong. Welcome to the real world of programming.

You'll have to learn how to deal with floating point numbers and roundoff errors, or learn how to use Arbitrary Precision Mathematics. There are plenty of articles on teh subject.

Anon

But shouldn't number_format() strip it down to 2 decimal places? I'm printing the number to the screen after number_format() has been run on it and I have also made sure that I am not running number_format() on a number which has alreay been formatted! I thought that's what the function was for??

Thanks for the response anyway. 🙂

Anon

Where did you see that number? I believe if you store the result of number_format() it will have what you want. Just calling number_format() won't change the variable unless you make an assignment:

<?php
$x = 0.001;
echo number_format($x, 2) . '<BR>';
echo $x . '<BR>';
$x = number_format($x, 2);
echo $x . '<BR>';
?>

Anon

Great thanks. 🙂

I was using it totally wrong. Thanks again. 🙂