> tmp <- matrix(1:12, 3, 4, dimnames=list(letters[1:3], LETTERS[1:4])) > tmp A B C D a 1 4 7 10 b 2 5 8 11 c 3 6 9 12 > tmp["a",, drop=FALSE] A B C D a 1 4 7 10 > tmp[,"A",drop=FALSE] A a 1 b 2 c 3 >
you need the correct number of commas. For your example > dim(out[1, drop=FALSE]) [1] 1 > out <- array(0, 5, list(1:5)) > dim(out) [1] 5 > dim(out[1]) NULL > dim(out[1, drop=FALSE]) [1] 1 > This construct usually isn't needed for assignment > out[2] <- 12 > out 1 2 3 4 5 0 12 0 0 0 > dim(out) [1] 5 > dim(out[2]) NULL > dim(out[2, drop=FALSE]) [1] 1 > 2012/1/31 Ernest Adrogué <nfdi...@gmail.com> > Hi there, > > This is a problem I've run into and do not know how to avoid. It > happens when I make an assignment using the dimension names as the > subscript of the array. The end result is a dimenensionless array > (i.e. a vector) which I don't want. See: > > > out <- array(0, 5, list(1:5)) > > dim(out) > [1] 5 > > out[names(out)] <- 1 > > dim(out) > NULL > > I tried to include a 'drop' argument into the index but it doesn't > seem to work: > > > out[names(out), drop=FALSE] <- 1 > Error in out[names(out), drop = FALSE] <- 1 : > incorrect number of subscripts on matrix > > A solution would be to change the vector into an array myself, but I > would like to hear opinions before I do that, because I would rather > just make the assignment and keep the array object unchanged if such > thing is possible. Also, using a subscript of integers instead of > labels is not an option in this case. > > Any help appreciated. > > -- > Cheers, > Ernest > > ______________________________________________ > 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<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > [[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.
