[R] -1.1 - 0.1 + 1.2 is NOT null! Why?

[massimodisasha]

Il 7/10/12 4:17 PM, ollestrat ha scritto:
> Hello,
>
> I fear its a stupid question,..but here it is:
>
> If I do this simple calculation with the R  console, I surprisingly do not
> get a zero. Why?
>
>   -1.1-0.1+1.2
> [1] -2.220446e-16
>
>
> greetings, Ole
>
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...

Python :
 >>> -1.1-0.1+1.2
-2.220446049250313e-16
 >>> -1.2-0.2+1.4
0.0
 >>>

R :
 > -1.1-0.1+1.2
[1] -2.220446e-16
 > -1.2-0.2+1.4
[1] 0
 >