I read through the suggestions below and they are great ones!

To summarize:
a)everything in Perl is a string until used in a numeric context.
b)Never, ever compare float values for equality in any languag!
c)If you compare $num1 < $num2 and both $num1 and $num2 can be converted to a number, then is is fine! If that is not true, then that's a problem.

I present here one of my subs that can compare text or numbers. This is not "perfect" and there are problems with say the "-" sign, but is a general idea.

sub alpha_num_cmp {
  my($a, $b) = @_;
  if (( $a =~ m/\D/) || ($b =~ m/\D/)) { #look for a non-digit
      return ($a cmp $b);              #if so, then use string compare
      }
 return ($a <=> $b);            #otherwise straight numeric comparison
}
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