Dear list, I have a matrix M.1 (30x2) into which I would like to paste another matrix M.2 (10x2) three times. However, the columns get flipped in every odd-numbered recycle run. How can I avoid this behavior? M.1 <- matrix(numeric(30*2), ncol = 2) M.2 <- t(combn(1:5, 2)) M.1[, 1:2] <- M.2 Many thanks for help, Alrik