[R] Unexpected behaviour of identical

[Peter Dalgaard]

"Swinton, Jonathan" <Jonathan.Swinton at astrazeneca.com> writes:

>  # works as expected
> > ac <- c('A','B');
> > identical(ac,ac[1:2])
> [1] TRUE
>  
>  #but
> > af <- factor(ac)
> > identical(af,af[1:2])
> [1] FALSE
> 
> Any opinions?

Hmm, surprising indeed. The proximate cause would seem to be that

> names(attributes(af))
[1] "levels" "class"
> names(attributes(af[1:2]))
[1] "class"  "levels"

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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