Hi structure of your data frame is not suitable for this task.
library(reshape) tutu.m<-melt(tutu, "nam") table(tutu.m$nam, tutu.m$value) art deb joy mar seb lio nem tat da 2 3 1 4 1 1 0 0 fr 2 2 2 3 0 1 1 1 ya 1 2 1 0 0 1 1 0 Regards Petr > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of Biau David > Sent: Friday, January 11, 2013 11:55 AM > To: r help list > Subject: [R] count combined occurrences of categories > > Dear all, > > i would like to count the number of times where I have combined > occurrences of the categories of 2 variables. > > For instance, in the dataframe below, i would like to know how many > times each author (au1, au2, au3 represent the first, second, third > author) is associated with each of the category of the variable 'nam'. > The position of the author does not matter. > > nam <- c('da', 'ya', 'da', 'da', 'fr', 'fr', 'fr', 'da', 'ya', 'fr') > au1 <- c('deb', 'art', 'deb', 'seb', 'deb', 'deb', 'mar', 'mar', 'joy', > 'joy') > au2 <- c('art', 'deb', 'mar', 'deb', 'joy', 'mar', 'art', 'lio', 'nem', > 'mar') > au3 <- c('mar', 'lio', 'joy', 'mar', 'art', 'lio', 'nem', 'art', 'deb', > 'tat') tutu <- data.frame(cbind(nam, au1, au2, au3)) > > thanks, > > David > [[alternative HTML version deleted]] ______________________________________________ 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.