From: PerlFAQ Server on
This is an excerpt from the latest version perlfaq4.pod, which
comes with the standard Perl distribution. These postings aim to
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4.2: Why is int() broken?

Your "int()" is most probably working just fine. It's the numbers that
aren't quite what you think.

First, see the answer to "Why am I getting long decimals (eg,
19.9499999999999) instead of the numbers I should be getting (eg,
19.95)?".

For example, this

print int(0.6/0.2-2), "\n";

will in most computers print 0, not 1, because even such simple numbers
as 0.6 and 0.2 cannot be presented exactly by floating-point numbers.
What you think in the above as 'three' is really more like
2.9999999999999995559.



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