Hi, May be this helps: res1<-as.matrix(transform(expand.grid(k1=0.3*(1:10),k2=1:10),k3=k1*k2)) A.K. Dear all, I'm trying to generate a matrix dataset following 2 loops analysis, such as the follows: for (i in 1:10) ?{ k1 <- 0.3 x i for (j in 1:10) ?{ k2 <- j k3 <- k1*k2 .... }} I would like to generate a dataset with each row containing k1, k2, and corresponding k3. As there's 100 combination of k1 and k2, so there would be 100 rows data. ?how could I do it? Thanks for the help. York