if($x==0){print "I'm ZERO!\n");

$x could come in as -0.00 or -9.049848394839e-14. We now have problems if your referring to say dollars and cents. I hear what you are saying ... I guess it is what it is.:o(

$x could come in as -0.00 or -9.049848394839e-14.

But you don't WANT -9.049848394839e-14 to be exactly equal to 0.

And that goes for any comparison between floats, which is why you need to specify your tolerance.

sub comp {
  my ($x,$y,$delta) = @_;
  $x -$delta >= $y && $x + $delta <= $y;
}
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"What should it profit a man, if he should win a flame war, yet lose his cool?"

Did you get the + and - swapped? Now comp(5, 4.5, 1) is false and comp(5, 4.5, -1) is true.

Personally I prefer to use the good old standard mathematical way of expressing it:

if (abs($x - $y) <= $tolerance) {
  print "$x and $y are 'equal'";
}
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lodin

$x could come in as -0.00 or -9.049848394839e-14.

It reminds me of the attempt to detect the soul, by weighing bodies before and after death. What a mess that concept is. :-)

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I'm not really a human, but I play one on earth. Cogito ergo sum a bum