[R] acos(0.5) == pi/3 FALSE

[Sundar Dorai-Raj]

Iñaki Murillo Arcos said the following on 9/18/2006 12:31 PM:
> Hello,
> 
>   I don't know if the result of
> 
>   acos(0.5) == pi/3
> 
> is a bug or not. It looks strange to me.
> 
>    Inaki Murillo
> 
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This is a FAQ:

http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f

 > acos(.5)
[1] 1.047198
 > pi/3
[1] 1.047198
 > acos(0.5) == pi/3
[1] FALSE
 > all.equal(acos(0.5), pi/3)
[1] TRUE

--sundar