I am confused by the question. Consider 
$x = 17;
for $i (1..10){
  $x = sqrt($x);
}
for $i (1..10){
  $x *= $x;
}
print $x;

[download]
prints 17.00000000000002 on my perl 5.005_003 on an x86. Is that an integer? merlin's comment shows how to see if a number is a "good" integer, but if you are using this in some mathematics, you might check for some fudge as it is fairly easy to get a non-integer that "should be" an integer.

You probably knew that, but it might not be obvious to everyone...

--traveler

In reply to Re: Integer detection concept by traveler
in thread Integer detection concept by boo_radley

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