That's because apply works on arrays/matrices, not data.frames.
It therefore coerces your data.frame to a matrix of type character, since you have factors, thus the result. You want sapply or lapply, since a data.frame is actually a list. sapply(df, class) and then to get what you want: df[sapply(df, is.factor)] Daniel Brewer wrote:
Hello, Is there a simple way to get the class type for each column of a data.frame? I am in the situation where I would like to get all the columns of a data.frame that are factors. I have tried: apply(df,2,class) but all the columns come back as class "character". Thanks Dan
______________________________________________ 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.
