> x=1:80 > > I want to sum up first 8 elements of x, then again next 8 elements of x, > then again another 8 elements..... So, my new vector should look like: > > c(36,100,164,228,292,356,420,484,548,612) > > I used: > > aggregate(x,list(rep(1:10,each=8)),sum)[-1] > > or > > rowsum(x,group=rep(1:10,each=8)) > > But without grouping, can I achieve the required? Any other ways of > doing this?
This works: colSums(matrix(x, nrow=8)) I'm not sure if you benefit over using the methods you described though. Regards, Richie. Mathematical Sciences Unit HSL ------------------------------------------------------------------------ ATTENTION: This message contains privileged and confidential inform...{{dropped:20}} ______________________________________________ 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.