[R] Levels number of a factor object

[Peter Dalgaard]

Laurent Houdusse <l.houdusse at cerep.fr> writes:

> Hi all!
> 
>     How to retrieve the levels number of a factor object?
>     See this code:
>     groups<-gl(4,10)
>     I want to retrieve the number of levels (4) of my object "groups"
>     I tried groups.levels but this don't work
> 
>     Thanks

Do you mean just

length(levels(groups))

?

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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