Changing the sign of a number in PHP?

Question

I have a few floats:

-4.50
+6.25
-8.00
-1.75

How can I change all these to negative floats so they become:

-4.50
-6.25
-8.00
-1         


        

Answer 1

How about something trivial like:

• inverting:

  $num = -$num;
  

• converting only positive into negative:

  if ($num > 0) $num = -$num;
  

• converting only negative into positive:

  if ($num < 0) $num = -$num;