Hi guys, my doubt is quite simple, I?ll try to explain: test = matrix(0, nrow = 783, ncol = 12) for (x in 1:9){ .... for (y in 1:12){ ### In the original script for each y its generated a vector (87x1) ### 87 times 9(x) = 783 (equals the number of rows I want to fill in the "test" matrix } } What I would like to do is to fill the "test" matrix with the "ys" in the collumns and the 87 elements of each x in the rows. for example, x = 1 y = 1 test[1:87, 1] = vector generated when y is 1 x = 2 y = 1 test [88:174,1] = another vector generated when y is 2 Could anybody help me? The script is quite long so i couldn?t just paste it here I think what i wrote above is undestandable. Thank you very much -- View this message in context: http://www.nabble.com/help-with-loops-tp25898891p25898891.html Sent from the R help mailing list archive at Nabble.com.