If you know all of the categories in advance, you can convert x and y to factors and then sum the tables:
> x<-1:4 > y<-2:5 > x <- factor(x , levels=1:5) # list all possible categories > y <- factor(y , levels=1:5) > table(x) x 1 2 3 4 5 1 1 1 1 0 > table(y) y 1 2 3 4 5 0 1 1 1 1 > table(c(x, y)) 1 2 3 4 5 1 2 2 2 1 > table(x) + table(y) x 1 2 3 4 5 1 2 2 2 1 ---------------------------------------------- David L Carlson Associate Professor of Anthropology Texas A&M University College Station, TX 77843-4352 > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of Francois Pepin > Sent: Monday, August 13, 2012 1:26 PM > To: r-help@r-project.org > Subject: [R] merge counts from table() > > Hi everyone, > > Is there an easy way to combine the counts from table()? > > Let's say that I have: > x<-1:4 > y<-2:5 > > I want to replicate: > table(c(x,y)) > > using only table(x) and table(y) as input. > > The reason is that it's cumbersome to carry all the values around when > all I care about are the counts. The actual situation has about a > billion counts over ~150 categories. > > I know there's got to be a number of ways of doing things (plyr comes > to mind), but I can't seem to find how to accomplish it. > > Thanks, > > François Pepin > ______________________________________________ > 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. ______________________________________________ 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.
