Full_Name: Stefan Albrecht Version: 2.2.0 OS: Windows XP Submission from: (NULL) (194.127.2.74)
Dear all, in the new R 2.2.0, the matrix indexing has been changed. In my opinion, this leads to an inconsistency when indexing one-row matrices. Take > (mat <- matrix(1:9, nrow = 3, dimnames = list(paste("r", 1:3, sep = ""), paste("c", 1:3, sep = "")))) c1 c2 c3 r1 1 4 7 r2 2 5 8 r3 3 6 9 Now taking the first row of the first-row of mat preserves the column names > mat[1, , drop = FALSE][1, ] c1 c2 c3 1 4 7 This is not true for the first column of the first-row of mat > mat[1, , drop = FALSE][, 1] [1] 1 However, for the first column of the first two rows of mat the row names are retained > mat[1:2, , drop = FALSE][, 1] r1 r2 1 2 This feature can lead to problems when indexing matrixes of different row numbers, since the row names are not preserved in all cases. I suggest to preseve the row names also for > mat[1, , drop = FALSE][, 1] Would it be possible to implement this feature? Many thanks. With best regards, Stefan Albrecht ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel