From murdoch at stats.uwo.ca  Tue Apr 24 13:27:47 2007
From: murdoch at stats.uwo.ca (Duncan Murdoch)
Date: Tue, 24 Apr 2007 07:27:47 -0400
Subject: [Rd] nlevels(<no factor>) is 0 and not NA
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Message-ID: <462DE9B3.6070604@stats.uwo.ca>

On 4/24/2007 4:58 AM, Torsten Hothorn wrote:
>> nlevels(c("a", "b"))
> [1] 0
> 
> but the documentation in R 2.5.0 (and earlier) says
> 
>  	If the argument is not a 'factor', 'NA' is returned.
> 
> I hope it isn't too late, I only came across this in a lecture this 
> morning.

It's too late for 2.5.0, but not for 2.5.1, or 2.6.0, ...

Just to be clear:  this is a documentation error, right?  The behaviour 
is unchanged back at least as far as 2.2.1.

Duncan Murdoch



[Rd] nlevels(<no factor>) is 0 and not NA
Duncan Murdoch