On Mon, Jan 18, 2010 at 10:33 AM, Ivan Calandra < ivan.calan...@uni-hamburg.de> wrote:
> I didn't understand from the help what really does the function rowMeans > but it looks like it doesn't take into account the categorical variables (I > want to calculate the means when the values of all categorical variables are > the same, second part of aggregate). Moreover, ssfa_num contains only > numeric variables, meaning that the categories will not be associated with > it. > I'm kind of confused with this approach. > You think it would work for me? > Conditional index to subset the data: ssfa_num_grp1 <- ssfa[10:24][CatCol == "Condition1"] ssfa_num_grp2 <- ssfa[10:24][CatCol2 == "Condition2"] Again to assign back to source dataframe: ssfa$mean[CatCol == "Condition1"] <- ssfa_num_grp1 It should be fairly straight forward to roll it into a loop thereafter. Ben [[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.