Hi Nevil, As I don't have the filematrix package this is really an "any suggestion":
FM[,which(colnames(FM) %in% c("one","three"))] Jim On Tue, Sep 8, 2020 at 9:43 PM nevil amos <nevil.a...@gmail.com> wrote: > > Is there a way to get columns out of a filematrix using the column name > directly in the same way that you can with a regular matrix? > > library(filematrix) > M<-t(matrix(1:3,3,4)) > colnames(M)<-c("one","two", "three") > M > #Extract column > M[,1] > M[,"one"] > M[,c(1,3)] > M[,c("one","three")] > FM<-fm.create.from.matrix(filenamebase = "test",mat = M) > FM[,1] > colnames(FM) > #extract by column by name does not work > FM[,"one"] > > #workaround using grep > #is there a more direct way of doing this to retrieve more than one column? > FM[,grep("one",colnames(FM))] > > FM[,c(grep("one",colnames(FM)),grep("three",colnames(FM)))] > > many thanks for any suggestions > > Nevil Amos > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.