[R] Comparing decimal numbers

[Eik Vettorazzi]

Hi Michael,
this is R-FAQ 7.31
http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f

cheers.

Am 01.02.2011 14:49, schrieb mlancee:
> 
> Hi,
> 
> I have a seemingly easy question that has been keeping be busy for quite a
> while. The problem is the following:
> 
> 0.1 + 0.1 + 0.1 == 0.3
> [1] FALSE
> 
> Why is this false? Another example is
> 
> 0.2 + 0.1 == 0.3
> [1] FALSE
> 
> or
> 
> 0.25 + 0.05 == 0.20 + 0.10
> [1] FALSE
> 
> However, I do get TRUE if I use integers, or for example the following
> 
> 0.1 + 0.1 == 0.2
> [1] TRUE
> 
> It is probably something very basic, but I did not manage to find the
> answer.
> 
> Thanks,
> Michael


-- 
Eik Vettorazzi
Institut für Medizinische Biometrie und Epidemiologie
Universitätsklinikum Hamburg-Eppendorf

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