[R] Setting rownames (was Please help.... i know its trivial)

[Prof Brian Ripley]

On Tue, 17 Apr 2007, Petr Klasterecky wrote:

> Patrick Callier napsal(a):
>> rownames is the command you want, I think.
>>
>> rownames(A) <- seq(1:8)
>>
>
> Yes. More generally
> rownames(A) <- 1:length(A[,1])

Better

rownames(A) <- seq_len(nrow(A))

which works correctly if the length is 0 or there are zero columns, and is 
self-explanatory.

Whenever you use 1:n you need to consider what you want if n <= 0.


> And keep in mind that nobody is going to help you next time, if you
> won't give a clear and informative SUBJECT in your message. Here it
> should have been something like 'wrong row names in subset' or
> 'dataframe subset question' etc, certainly not 'please help me, it's
> trivial'...
>
> Btw, there is something like the posting guide for this list (see footer).

And please change the subject line to something appropriate when replying.

>
> Petr
>
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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