Hello everybody!
I have a (probabely very easy) problem. Even though I was looking in
several r-books
I could not find a suitable function to this problem, that's why I hope
that someone here
could help me:
# Sample data:
group<-c("A","A","A","B","B","C","C","C")
var1<-c(1,0,0,1,1,0,NA,1)
var2<-c(0,1,NA,0,1,1,0,0)
testdata<-data.frame(group, var1, var2)
Now, I'd like to generate two aggregated variables:
testdata$x<- ??? should count the sum of var1 within each group (=4)
testdata$y<- ??? should count the sum of var2 within each group (=3)
Therefore I am looking for a function like ave() which does not calculate
the mean value but a sum.
Thank you for any hints!
David
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
