Dear Fellow Rers, I have a table looks like this:
ca, la, 12 ca, sd, 22 ca, la, 33 nm, al, 9 ma, lx, 18 ma, bs, 90 ma, lx, 22 I want to sum the 3rd column grouped by the first and the second column, so the result look like this table: ca, la, 45 < ca, sd, 22 nm, al, 9 ma, lx, 40 < ma, bs, 90 The two rows with < are sums. I tried aggregate(table,list(table$V1,table$V2),sum/mean), sum was not working while mean worked. Can anybody give a hint? Thanks. Guanrao ______________________________________________ R-help@stat.math.ethz.ch 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.
