You need to define how much digits you count as significant. There are lots of examples where it's noted that you can't directly compare floats with each other. Do something along this lines: 
print "The numbers $foo and $bar are significant different!"
   if (abs($foo - $bar) >= (10**-10));

[download]
Adjust the power to your likes.

Update: Of course it should be >=, thanks Eureka_sg. Somehow I seemed to have thought about using unless but wrote if instead...
--
use signature; signature(" So long\nAlfie");

In reply to Re: Strange (rounding?) problem by alfie
in thread Strange (rounding?) problem by gildir

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