the reshape package might also help: > require(reshape) > x A B C D E 1 1 6 11 16 21 2 2 7 12 17 22 3 3 8 13 18 23 4 4 9 14 19 24 5 5 10 15 20 25 > melt(t(x)) X1 X2 value 1 A 1 1 2 B 1 6 3 C 1 11 4 D 1 16 5 E 1 21 6 A 2 2 7 B 2 7 8 C 2 12 9 D 2 17 10 E 2 22 11 A 3 3 12 B 3 8 13 C 3 13 14 D 3 18 15 E 3 23 16 A 4 4 17 B 4 9 18 C 4 14 19 D 4 19 20 E 4 24 21 A 5 5 22 B 5 10 23 C 5 15 24 D 5 20 25 E 5 25
On Tue, Jan 20, 2009 at 9:10 AM, Antje <niederlein-rs...@yahoo.de> wrote: > Hello, > > I have a question how to reshape a given matrix to a data frame. > > # ---------------------------------- >> a <- matrix(1:25, nrow=5) >> a > [,1] [,2] [,3] [,4] [,5] > [1,] 1 6 11 16 21 > [2,] 2 7 12 17 22 > [3,] 3 8 13 18 23 > [4,] 4 9 14 19 24 > [5,] 5 10 15 20 25 > >> colnames(a) <- LETTERS[1:5] >> rownames(a) <- as.character(1:5) >> a > A B C D E > 1 1 6 11 16 21 > 2 2 7 12 17 22 > 3 3 8 13 18 23 > 4 4 9 14 19 24 > 5 5 10 15 20 25 > > # ----------------------------------- > > This is an example on how my matrix looks like. > Now, I'd like to reshape the data that I get a data frame with three > columns: > > - the row name of the enty (X1) > - the column name of the entry (X2) > - the entry itself (X3) > > like: > > X1 X2 X3 > 1 A 1 > 2 A 2 > 3 A 3 > .... > 1 B 6 > 2 B 7 > .... > 5 E 25 > > How would you solve this problem in an elegant way? > > Antje > > ______________________________________________ > 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 that 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.
