A is not a matrix. I presume you meant B. If so: > B[!C] <- 0 > B [,1] [,2] [,3] [,4] [1,] 1 6 0 0 [2,] 2 0 0 0 [3,] 3 0 0 0 [4,] 4 0 0 19 [5,] 5 0 0 0
Cheers, Bert On Sat, Sep 5, 2020 at 11:18 AM Vivek Sutradhara <viveksu...@gmail.com> wrote: > Hi > I would like to get help in combining two matrices. Here is my example: > A <- 1:20 > B <- matrix(A,nrow=5,ncol=4) > # B is a numerical matrix > C <- B<7 > C[4,4] <- TRUE > # C is a logical matrix > # if I combine A and C, I get a vector > D1 <- A[C==TRUE] > D1 > D2 <- A[C==FALSE] > D2 > > I want to get a matrix with the same dimensions as matrix A. At the > coordinates given by the vector D1, I want to retain the values in > matrix A. At the locations in D2, I want a zero value. > I want to know if I can do this without using any loops. > Thanks, Vivek > > [[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. > [[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.