FAQ 4.1 Why am I getting long decimals (eg, 19.9499999999999) instead of the numbers I sho...

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4.1: Why am I getting long decimals (eg, 19.9499999999999) instead of the
numbers I should be getting (eg, 19.95)?

    For the long explanation, see David Goldberg's "What Every Computer
    Scientist Should Know About Floating-Point Arithmetic"
    (http://docs.sun.com/source/806-3568/ncg_goldberg.html ).

    Internally, your computer represents floating-point numbers in binary.
    Digital (as in powers of two) computers cannot store all numbers
    exactly. Some real numbers lose precision in the process. This is a
    problem with how computers store numbers and affects all computer
    languages, not just Perl.

    perlnumber shows the gory details of number representations and

    To limit the number of decimal places in your numbers, you can use the
    "printf" or "sprintf" function. See the "Floating Point Arithmetic" for
    more details.

            printf "%.2f", 10/3;

            my $number = sprintf "%.2f", 10/3;


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