Jason - colSums does return an object of class "numeric", which is certainly a vector. The vector it returns happens to have names. If you want an unnamed vector of the sums, just set the names attribute to NULL. This will remove the names. However, you say you can't figure out how to index the object that colSums returns. You index it just like any other vector, but you can use names in addition.
## ALL UNTESTED! ## test data.frame testdf <- data.frame(a = rnorm(10), b = rnorm(10)) cs <- colSums(testdf) class(cs) ## numeric is.vector(cs) ## TRUE names(cs) ## look at the names of the vector cs[1] ## first element of cs cs["a"] ## same as above ## get rid of names attribute names(cs) <- NULL cs ## look at cs, no more names cs[1] ## still works cs["a"] ## no longer works Best, Erik Iverson Jason Horn wrote: > Does anyone know how to get a vector of column sum from a data frame? > You can use colSums(), but this gives you a object of type "numeric" > with the column labels in the first row, and the sums in the second > row. I just want a vector of the sums, and I can't figure out a way > to index the "numeric" object. > > Thanks! > > ______________________________________________ > 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.
