Sorry, that should be t(a[as.logical(j), as.logical(j)])
Rui Barradas Em 26-10-2014 18:45, Rui Barradas escreveu:
Hello, Try the following. a[as.logical(j), as.logical(j)] # or b <- a[as.logical(j), ] t(b)[as.logical(j), ] Hope this helps, Rui Barradas Em 26-10-2014 18:35, Steven Yen escreveu:Dear I am interested in selecting rows and columns of a matrix with a criterion defined by a binary indicator vector. Let matrix a be > a<-matrix(1:16, 4,4,byrow=T) > a [,1] [,2] [,3] [,4] [1,] 1 2 3 4 [2,] 5 6 7 8 [3,] 9 10 11 12 [4,] 13 14 15 16 Elsewhere in Gauss, I select the first and third rows and columns of a by defining a column vector j = [1,0,1,0]. Then, select the rows of a using j, and then selecting the rows of the transpose of the resulting matrix using j again. I get the 2 x 2 matrix as desired. Is there a way to do this in R? below are my Gauss commands. Thank you. --- j 1 0 1 0 a=selif(a,j); a 1 2 3 4 9 10 11 12 a=selif(a',j); a 1 9 3 11 ______________________________________________ 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.______________________________________________ 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.
______________________________________________ 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.
