similar to: Loss of rownames and colnames

I noticed something surprising (in R 2.2.1 on WinXP) According to the documentation, rownames and colnames are character vectors. Assigning a vector of class POSIXct or POSIXlt as rownames or colnames therefore is not strictly according to the rules. In some cases, R performs a reasonable typecast, but in some other cases where the same typecast also would be possible, it does not. Assigning a

I noticed something surprising (in R 2.2.1 on WinXP) According to the documentation, rownames and colnames are character vectors. Assigning a vector of class POSIXct or POSIXlt as rownames or colnames therefore is not strictly according to the rules. In some cases, R performs a reasonable typecast, but in some other cases where the same typecast also would be possible, it does not. Assigning a

Looking into several different parts of R../src/library/base/R/*.R has led me to the conclusion that quite a bit of code doubling could be saved by using the following two functions whose naming philosophy is derived from that of NROW() & NCOL(): COLNAMES <- function(x) if(is.null(n <- colnames(x))) paste(seq(length=NCOL(x))) else n ROWNAMES <- function(x)

The help text for row+colnames {base} states: "For a data frame, rownames and colnames eventually call row.names and names respectively, but the latter are preferred." Why are they "preferred"? Why is it names(), not col.names()? I have only ever used names() for vectors - I'm surprised it works on data.frames... IMO this is not great for code readability, thus

Hi all I was wondering whether there has ever been an update on the rownames and colnames behaviour as described by Eric below? I still get the same behaviour, exactly as described by Eric, on my WinXP installation of R-2.3.0. I also posted a message to r-help on Friday but looking through the online archives it seems to have not made it to the list. I would agree with Eric that a consistent

There's a bit of a symmetry issue, which may or may not be important (led to 15 seconds of confusion until I got my bearings straight): row.names, rownames; colnames, no col.names? I _NOW_ realize the difference between row.names and rownames, but is there any reason not to have col.names for re-naming columns in a data.frame? (if there is, I don't particular need to know it, but it

Data frames are lists of columns. The names() function is appropriate for lists. It doesn't pay to fall into the trap of thinking that data frames are truly symmetric between columns and rows, because there is a performance penalty for accessing rows that is greater than the cost of accessing columns. With that in mind, thinking of data frames as lists is preferred, so names is preferred

Full_Name: Tomas Larsson Version: 2.6.0 OS: Windows XP Submission from: (NULL) (198.208.251.24) This is not a bug, it is a performance issue but I think it should have an easy fix. I have a large matrix (about 2,000,000 by 20), when I type colnames(x) it takes a long time to get the result. However, if I select just the first couple of rows of the matrix I don't have to wait for the

I'm trying to massage some data from Matlab into R. The matlab file has a "struct array" which when imported into R using the R.matlab package, becomes an R list with 3+ dimensions, the first of which corresponds to the structure fields, with corresponding row names, and the second and third+ dimensions correspond to the dimensions of the original struct array (as matlab

Hi all, How get colnames and rownames in Rcpp method? attecthed file : RGui.exe capture my work environment : R version : 2.11.1 OS : WinXP Pro sp3 Thanks and best regards. Young-Ju, Park from Korea [1][rKWLzcpt.zNp8gmPEwGJCA00] [@from=dllmain&rcpt=r%2Dhelp%40r%2Dproject%2Eorg&msgid=%3C20100728211143%2EH

Hello! Data.frames have new rownames funcionality, however in use of colnames<- in R-devel "changes" this. Here is the example: > df1 <- data.frame(letters[1:5]) > attributes(df1) $names [1] "letters.1.5." $row.names [1] 1 2 3 4 5 $class [1] "data.frame" > colnames(df1) <- "bla" > attributes(df1) $names [1] "bla"

Hello, I'm hoping someone with a wide experience with R may be able to see what the program is trying to tell me. I've got an array: y1=rnorm(41,0.2) y2=rnorm(41,0.2) y3=rbind(y1,y2) data11<-array(0,c(41,2,2)) data11[,1,]=y3 data11[,2,]=y3 rownames(data11)<-rownames(data11, do.NULL = FALSE, prefix = "Obs.") colnames=c("V","R")

Hello, I have another stupid question. I hope you can give me a hint how to solve this: I have a list and one element is again a list containing matrices, all of the same dimensions. Now, I'd like to set the dimnames for all matrices: example code: m1 <- matrix(1:25, nrow=5) m2 <- matrix(26:50, nrow=5) # ... there can be much more than two matrices l <- list() l[[1]] <-

Dear all, I have a data frame of dimension 720 columns by 360 rows, to which I am trying to add numerical row and column labels to, using the 'sequence' command. The original data, which I read in using 'read.table', had no such labels at all. I've got as far as successfully using the sequence command and getting the labels to display. However, I'm finding that for the

Hi every one, How is it possible to create a matrix with 3 dimensions from several 2 dimensional matrice? Is it possible that each of "elementary/building block" matrices could be called by its corresponding original name? Thanks alot. -- View this message in context:

Hi, I have a matrix with column names starting with a character in [0-9]. After some matrix operations (e.g. copy to another matrix), R seems to add a character 'X' in front of the column name. Is this a normal default behaviour of R? Why has it got this behaviour? Can it be changed? What would be the side effect? Thank you. Regards, Gilbert [[alternative HTML version deleted]]

Full_Name: Axel Rasche Version: 2.1.0 OS: Win2000 Submission from: (NULL) (141.14.21.81) Hi, write.table does not accept the second statement with <col.names = NA, row.names = FALSE>. I do not see why this should not be possible. test = matrix(1:4, 2, 2, dimnames = list( c("a","b"), c("c","d") )) write.table(test, file = "test.txt",

Hi I want to extract rows of a matrix, and preserve rownames even if only one row is selected. Toy example: R> a <- matrix(1:9,3,3) R> rownames(a) <- letters[1:3] R> colnames(a) <- LETTERS[1:3] R> a A B C a 1 4 7 b 2 5 8 c 3 6 9 Extract the first two rows: R> wanted <- 1:2 R> a[wanted,] A B C a 1 4 7 b 2 5 8 rownames come through fine. Now extract just

An NA in the rownames of a matrix (or dataframe) causes misalignment when the matrix is printed: R> x <- matrix(1:12, 3,4, dimnames=list(letters[1:3], LETTERS[1:4])) R> rownames(x)[2] <- NA R> x A B C D a 1 4 7 10 <NA> 2 5 8 11 c 3 6 9 12 The bug is in function Rstrlen, in src/main/printutils.c. MatrixRowLabel and MatrixColumnLabel (same file) rely on Rstrlen

Hi, I'm quite new to R, so excuse me if this problem has a simple solution. I'm working with an array, lets say i <- array(c(1:3,3:1), dim=c(3,2)) Then I want to give the rows and the columns names: rownames(i)<-c("a","b","c") colnames(i)<-c("d","e") The result is given below: d e a 1 3 b 2 2 c 3 1 Here comes my problem.