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

This message is one of several periodic postings to comp.lang.perl.misc
intended to make it easier for perl programmers to find answers to
common questions. The core of this message represents an excerpt
from the documentation provided with Perl.

--------------------------------------------------------------------

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

    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.

    the perlnumber manpage show the{*filter*}details of number representations
    and conversions.

    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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Sat, 18 Jun 2005 12:00:48 GMT  
 
 [ 1 post ] 

 Relevant Pages 

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

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

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

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

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

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

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

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

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

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

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

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

 

 
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