Dear all,
I have the following R dataframe:
set.seed(11)
(df <- data.frame(ID=rep(1:10,1:10),a=factor(sample(1:4,55,rep=T)) ))
where ID is an identification code.
I need to create a new variable "b" in which I would paste the full group
of "a" variable according to ID variable.
For example for ID=2 "b" should be 13, for ID=3 "b" should be 114, and
for ID=4 should be 1241.
How can I do that ?
Thank you for any advices,
Regards,
Massimiliano Tripoli
[[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.
