Sorting a matrix by a column
On Mon, 4 Aug 2008, John Sorkin wrote:
R 2.6 Windows XP I have a 100x4 matirx data<-matrix(nrow=100,ncol=4) I would like to sort the entire matrix by column two, i.e. data[,2] I looked at the help page for sort() but can not determine how I can use it to sort a matrix on one of the matrix's columns.
Rather, use sort.list, e.g. data[sort.list(data[,2]), ] There's an example for data frames on ?order.
Thanks,
John
John David Sorkin M.D., Ph.D.
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