What you are doing with the assignment m[,c(1,2)] <- m[,c(2,1)]
is only changing the values in the matrix; it knows nothing about the names. If you want the names of the columns switched, then you have to do it: > m <- cbind(x=1:3, y=2:4, z=3:5) > m x y z [1,] 1 2 3 [2,] 2 3 4 [3,] 3 4 5 > m[,c(1,2)] <- m[,c(2,1)] > m x y z [1,] 2 1 3 [2,] 3 2 4 [3,] 4 3 5 > colnames(m)[c(1,2)] <- colnames(m)[c(2,1)] > m y x z [1,] 2 1 3 [2,] 3 2 4 [3,] 4 3 5 > On Mon, Jun 16, 2008 at 8:10 AM, Daren Tan <[EMAIL PROTECTED]> wrote: > > How can I swap the column names at the same time ? > >> m <- cbind(x=1:3, y=2:4, z=3:5)> m x y z[1,] 1 2 3[2,] 2 3 4[3,] 3 4 5 >> m[,c(1,2)] <- m[,c(2,1)]> m x y z[1,] 2 1 3[2,] 3 2 4[3,] 4 3 5 > _________________________________________________________________ > > > [[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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem you are trying to solve? ______________________________________________ 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.