Try melt from the reshape package: library(reshape) melt(DF, 1:2)
You may may need to resort it if the order is important. On 5/15/06, YIHSU CHEN <[EMAIL PROTECTED]> wrote: > Dear R folks: > > I wonder anyone has a elegent way of doing what I need to do. > > I have a data frame called with four columns: V1, V2, A1 and A2: > > V1 V2 A1 A2 > A B 1.2 2.0 > A D 1.2 4.0 > A C 2.4 2.2 > > What I need to do is to convert it into the following data frame with a new > column x, where x is just the stacked up of A1 and A2 placed with respective > V1 and V2 in the first two columns: > > V1 V2 x > A B 1.2 > A B 2.0 > A D 1.2 > A D 4.0 > A C 2.4 > A C 2.2 > > I wonder whether there is an efficient way to do it since I have huge dataset. > > Thank you very much > > Yihsu > > > > > > > > > > > > > > > > > > > > > > Yihsu Chen > The Johns Hopkins University > > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
