[R] How to refer to the last a few rows?

[Peng Yu]

On Mon, Sep 14, 2009 at 9:37 AM, baptiste auguie
<baptiste.auguie at googlemail.com> wrote:
> Hi,
>
>
> tail(x,2)

Is there a convenient function like 'tail()' to extract last a few
columns? I can use t(tail(t(x),2)). But I feel convenient if there is
a function can give me such thing directly.

> or
>
>  x[seq(nrow(x)-1, nrow(x)), ]
>
>
> HTH,
>
> baptiste
>
> 2009/9/14 Peng Yu <pengyu.ut at gmail.com>
>>
>> Hi,
>>
>> x=matrix(1:60,nr=6)
>>
>> I can refer the last 2 rows by
>> x[5:6,]
>>
>> If I don't know the total number of rows is 6, is there a way to refer
>> the last 2 rows?
>>
>> Regards,
>> Peng
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
>
>
> --
> _____________________________
>
> Baptiste Auguié
>
> School of Physics
> University of Exeter
> Stocker Road,
> Exeter, Devon,
> EX4 4QL, UK
>
> http://newton.ex.ac.uk/research/emag
> ______________________________
>
>