From h.wickham at gmail.com  Tue Nov 11 20:48:00 2008
From: h.wickham at gmail.com (hadley wickham)
Date: Tue, 11 Nov 2008 13:48:00 -0600
Subject: [Rd] is.matrix
In-Reply-To: <4919E010.8080603@idi.ntnu.no>
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	<4919E010.8080603@idi.ntnu.no>
Message-ID: <f8e6ff050811111148m773ec9d3x22cbabd8efa8b51c@mail.gmail.com>

On Tue, Nov 11, 2008 at 1:42 PM, Wacek Kusnierczyk
<Waclaw.Marcin.Kusnierczyk at idi.ntnu.no> wrote:
> hadley wickham wrote:
>>> |  is.matrix| returns |TRUE| if |x| is a matrix and has a |dim <dim.html>|
>>> attribute of length 2) and |FALSE| otherwise
>>>
>>
>> That's confusing!  In what situations is x a matrix but does not have
>> a dim attribute?
>>
>>
>
> x = matrix(1,1,1)
> dim(x) = c(1,1,1)

I think you meant
dim(x) <- c(3, 1)

You created a 1 x 1 x 1 array.

Hadley

-- 
http://had.co.nz/



[Rd] is.matrix
hadley wickham