What exactly are you trying to do? An example (which you should have provided!!!!)
> A <- matrix(1:100,nrow=10,ncol=10) > B <- A[10,1:3] > B [1] 10 20 30 > is.matrix(B) [1] FALSE > matrix(B) [,1] [1,] 10 [2,] 20 [3,] 30 This is logic, as you convert a vector to a matrix, and he will assume you have one column. If you transform it, you should do : > matrix(B,ncol=3) [,1] [,2] [,3] [1,] 10 20 30 Or use drop=F : > C <- A[10,1:3,drop=F] > C [,1] [,2] [,3] [1,] 10 20 30 > is.matrix(C) [1] TRUE On Wed, May 26, 2010 at 5:58 PM, <mau...@alice.it> wrote: > I am assigning subset of a matrix A [n,3] where n>1 to a temporary matrix > TMP > I do not know how many rows of A will be assigned to TMP because this is > established by a > run-time test. > I expect TMP to be a matrix [m,3], m >=1 > But when 1 row only is transferred from A to TMP then TMP becomes [3,1] > rather than [1,3] > How can I avoid this unwanted transpose operation ? > > THank you in advance, > Maura > > > tutti i telefonini TIM! > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@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. > -- Joris Meys Statistical Consultant Ghent University Faculty of Bioscience Engineering Department of Applied mathematics, biometrics and process control Coupure Links 653 B-9000 Gent tel : +32 9 264 59 87 joris.m...@ugent.be ------------------------------- Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php [[alternative HTML version deleted]] ______________________________________________ R-help@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.