in reply to Re^2: False positive on inequality comparison
in thread False positive on inequality comparison

Using string comparison on floats is dangerous, unless you don't care if the floats are actually different!

As this shows in the last line, Perl's default stringification for floats will only show you 6 decimal places of precision, anything beyond that accuracy and you are just pretending the are the same. 

$first = unpack 'd', pack 'b64', 
'1001110001010011100010111001000010000101000001010110011000000010';;

$second = unpack 'd', pack 'b64', 
'1010110001010011100010111001000010000101000001010110011000000010';;

printf "%f %f :> %17.17f\n", $first, $second, $first - $second;;
181.019658 181.019658 :> 0.00000000000011369

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