search for: completedf

Hi, With two data sets, one complete and another one partial, I would like to merge them and keep the unmatched lines. The problem is that merge() dosen't keep the unmatched lines. Is there another function that I could use to merge the data frames. Example: completedf <- expand.grid(alpha=letters[1:3],beta=1:3) partdf <- data.frame( alpha= c('a','a','c'), beta = c(1,3,2), val = c(2,6,4)) mergedf <- merge(x=completedf, y=partdf, by=c('alpha','beta')) # it only kept the common rows nrow(mergedf) Thanks, Etienn...