Thank you guys for your suggestions! Florent D - that probably is the way of writing what I had in my head. The suggestion I took up was one of JHoltman's which he put in an e-mail to me following his initial post but it works well with the vectors in this question:
require(plyr) x1.6 <- laply(1:6, function(a) get(paste('x', a, sep = ''))) rowMeans(x1.6) It is nice because it's easily extendable to matrices too which I want to do later - change rowMeans(x1.6) to colMeans(x1.6). Thank you all for your help, Pablo -- View this message in context: http://r.789695.n4.nabble.com/Summing-x1-to-x6-tp4214604p4216977.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.