[Libreoffice-qa] fdo#80638 "Incorrect SUM with decimal numbers"

[Jay Lozier]

On 06/29/2014 12:53 PM, Terrence Enger wrote:
> Hi, all.
>
> I have just, for the first time that I remember, changed a confirmed bug
> report to a request for enhancement.  I would like confirmation or
> correction of my judgement.
>
> The report is fdo#80638 "Incorrect SUM with decimal numbers"
> <https://bugs.freedesktop.org/show_bug.cgi?id=80638>.  My thought is
> that Calc simply does not do decimal numbers.
>
> Thanks for your attention,
> Terry.
Hi,

This is not an LO bug. I get the exact same result with a Python script, 
a Ruby script, and Calligra Sheets.

It is a problem with internal representation of decimal numbers in any 
computer system. This is a well known problem in scientific 
computing/numerical analysis.

Also, reordering the addition produced different precisions. I think the 
correct numerical analysis term for this is precision referring to how 
closely the actual value is to the true value.

I would close this report with the note this is not a problem specific 
to LO or any other spreadsheet. All spreadsheets will produce similar 
results depending on the specifics of how real numbers are handled by 
the underlying OS/CPU.

Jay

-- 
Jay Lozier
jslozier at gmail.com