Hello Julia, Your loop is just "overwriting" your variables each time.
Is this the sort of thing you want ? # make a matrix with 10 cols of N random uniform values N <- 5 x <- t( replicate( 10, runif(N, 0, 1) ) ) You can leave out the t( ... ) part if you want the randomizations to be rows instead of cols Michael On 6 October 2010 20:51, Julia Lira <julia.l...@hotmail.co.uk> wrote: > > Dear all, > > > > I need to do a loop in R, but I am not sure the software is generating "n" > times the variables I request differently. When I ask to print the last > matrix created, I just can see the loop for n=1. > > To be more precise, supose I need to simulate 10 times one variable and I > want to fit the 10 variables simulated in a matrix. I dont really know what I > am doing wrong, but I just can see 1 variable created. > > Below follows an example of what I want: > > > > rm(list=ls()) #remove almost everything in the memory > > > > set.seed(180185) > > > > #loop: create 10 times the variables (u1,u2,u3,u4,u5) > > > > for (i in 1:10){ > u1 <- c(runif(200,0,1)) > u2 <- c(runif(200,0,1)) > u3 <- c(runif(200,0,1)) > u4 <- c(runif(200,0,1)) > u5 <- c(runif(200,0,1)) > u <- c(u1,u2,u3,u4,u5) > mu <- matrix(u, nrow=1000, ncol=1) > } > > > As you can see, when I print(mu), I just can see a matrix with the vector u > in one column. I also tried to increase the number of columns to 10 (or i), > but the matrix will have 10 times the same vector. And what I need is like a > Monte Carlo simulation, where I have to simulate 10 times the variables above. > > > > Am I doing something wrong? > > > > Thanks in advance! > > > > Julia > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > ______________________________________________ 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.