I do not think that reversing the hash helps. In any case you should define a function that returns true (ie 1) if the argument is (approximately) an integer and then do a grep on the \@zeroes. 

# untested
sub is_approximately_an_integer {
  my $x = shift;
  my $eps = 0.0001;
  return abs( $x-round($x) ) < $eps;
}

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In reply to Re^3: question about what to grep(?) by hdb
in thread question about what to grep(?) by crunch_this!

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