[Tom Cohen] > I have the following dataset and want to know how many times each value > occur in each column.
> >data > [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] > [1,] -100 -100 -100 0 0 0 0 0 0 -100 > [2,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [3,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [4,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [5,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -50 > [6,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [7,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [8,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > [9,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[10,] -100 -100 -100 -50 -100 -100 -100 -100 -100 -100 >[11,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[12,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[13,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[14,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[15,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[16,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[17,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[18,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 >[19,] -100 -100 -100 0 0 0 0 0 0 -100 >[20,] -100 -100 -100 -100 -100 -100 -100 -100 -100 -100 > The result matrix should look like > -100 0 -50 >[1] 20 >[2] 20 >[3] 20 >[4] 17 >[5] 18 >[6] 18 >[7] 18 and so on >[8] >[9] >[10] Presuming that "data" is a matrix, one could try a sequence like this: dataf <- factor(data) dim(dataf) <- dim(data) result <- t(apply(dataf, 2, tabulate, nlevels(dataf))) colnames(result) <- levels(dataf) result If you want the columns sorted, you might decide the order of the levels on the "factor()" call, or explicitly reorder columns afterwards. -- François Pinard http://pinard.progiciels-bpi.ca ______________________________________________ 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.