Dear Roman,
You can use unique(X, MARGIN=2). See ?unique for details.
I hope this helps,
John
--------------------------------
John Fox
Department of Sociology
McMaster University
Hamilton, Ontario
Canada L8S 4M4
905-525-9140x23604
http://socserv.mcmaster.ca/jfox
--------------------------------
> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Roman
> Akhter Ahmed
> Sent: Monday, December 18, 2006 8:42 PM
> To: r-help at stat.math.ethz.ch
> Subject: [R] unique columns of a matrix
>
> Dear all,
>
> I have a matrix of repeating columns in R, for example a matrix X is
>
> [,1] [,2] [,3] [,4]
> [1,] 1 1 1 1
> [2,] 1 1 2 2
>
> I want to store unique columns of the matrix X in a new matrix Y.
> Therefore, Y will be
>
> [,1] [,2]
> [1,] 1 1
> [2,] 1 2
>
> It will be really appreciated if you can provide me some
> function for this job.
> Thanks for your time and effort in advance, Roman
>
> --
> ----------------------------------------------------------------------
> Roman Akhter Ahmed (Ph.D. Candidate)
> Department of Econometrics and Business Statistics Room 659,
> Building 11 (East Wing), Clayton Campus Monash University,
> Victoria 3800, Australia
> Ph.: +61 3 9905 8346 (W), +61 3 9543 1958 (R)
> Web: http://www.buseco.monash.edu.au/staff/profile.php?uid=rahmed
> ----------------------------------------------------------------------
>
>