Thanks for all the replies. The merge solution is what I was groping toward but the factor solution is much cleaner since I do know in advance what the possible categories are.
François On Aug 14, 2012, at 2:39 , PIKAL Petr wrote: > Hi > > If your x and y are factors it seems to be easy, just add all levels in both. > > x.f<-factor(x, levels=1:5) > y.f<-factor(y, levels=1:5) > > table(x.f)+table(y.f) > x.f > 1 2 3 4 5 > 1 2 2 2 1 > > If you just have output from table(x) without possibility to add levels you > can go with merge > > >> mm <- merge(as.data.frame(table(x)), as.data.frame(table(y)), by.x="x", >> by.y="y",all=T) > x Freq.x Freq.y > 1 1 1 NA > 2 2 1 1 > 3 3 1 1 > 4 4 1 1 > 5 5 NA 1 > > Here you need to change NA to 0 and perform rowSums. > > mm[is.na(mm)]<-0 > rowSums(mm[-1]) > [1] 1 2 2 2 1 > t(cbind(mm[,1],rowSums(mm[-1]))) > [,1] [,2] [,3] [,4] [,5] > [1,] 1 2 3 4 5 > [2,] 1 2 2 2 1 > > Regards > Petr > >> 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.
