221816 - wrong sum

Status: VERIFIED DUPLICATE of bug 20140

(Core :: JavaScript Engine, defect)

Description

[Roger C. Soares]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; pt-BR; rv:1.4) Gecko/20030624 Netscape/7.1
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; pt-BR; rv:1.4) Gecko/20030624 Netscape/7.1

doing 1.1 + 2.2 in javascript isn't returning 3.3 as expected, it returns
3.3000000000000003

It also happens with 10.1 + 20.2 and 100.1 + 200.2

To simply reproduce, type on the location bar:
javascript:alert(1.1 + 2.2);


Reproducible: Always

Steps to Reproduce:

Comment 1

[Jo Hermans]

Mozilla is following the appropriate standards here--the issue centers around
trying to represent base-10 numbers in a computer that does base-2 math.  See
the references in bug 20140 for more info. You'll have to round up (w/ 2 digits
after the decimal point) before you present it to the user.

PS : same 'error' in Internet Explorer ... that should make you think.



*** This bug has been marked as a duplicate of 20140 ***

Comment 2

[Roger C. Soares]

konqueror doesn't have this 'error'... must open a bug to fix it! ;)

Thanks for the info.

Comment 3

[zack-weg]

> konqueror doesn't have this 'error'... must open a bug to fix it! ;)

FYI: There is a KDE bug for rounding the wrong way, and it has been marked fixed
last week: http://bugs.kde.org/show_bug.cgi?id=51684 . Konqueror 3.2 should behave
exactly as Mozilla, Opera and IE do.