PHP negatives keep adding - php

Question

I have this code here...
$remaining = 0;
foreach($clientArrayInvoice as $key=>$row){
$remaining = $remaining + $row['total'];
}
What it does, it takes the values of total and adds them up...but when I have values that are negatives, it adds them up as well for an example when I have -51.75 and -17.85 I get -69.60 which it should be -33.90 how do I fix this?
`-33.901 is the value I am expecting because when its two negatives I would like to subtract, not add
Thanks,
J

Answer 1

This might help:
(-51.75) + (-17.85) = -69.60
(-51.75) - (-17.85) = -33.90
Assuming you always need to add the second number regardless of it's sign, you need to take the absolute value by using the PHP abs function with $row['total']:
$remaining = 0;
foreach($clientArrayInvoice as $key=>$row){
$remaining = $remaining + abs($row['total']);
}
In response to what you updated in your question:
-33.90 is the value I am expecting because when its two negatives I would like to subtract, not add
This is pretty much what using the abs function does. I could rewrite the above code snippet as:
$remaining = 0;
foreach($clientArrayInvoice as $key=>$row) {
if ($remaining >= 0) {
$remaining = $remaining + abs($row['total']);
}
else {
$remaining = $remaining - abs($row['total']);
}
}
However, this does the exact same thing as simply using the PHP abs function, since you are always adding the magnitude of $row['total'] to $remaining.

Answer 2

again --> see php's abs() function if you want to add things and ignore the sign.

Answer 3

I am not sure what your question is exactly, but this would keep adding the absolute values if $remaining is negative until it is positive again.
$remaining = $remaining + ($remaining < 0 && $row['remainingbalance']
< 0 ? -1 : 1) * $row['remainingbalance']);
This works for your example, it would be 0 - 51.75 + 17.85 = -33.9. But I am not sure if it's the behavior you want in the bigger picture.