similar to: Characters vectors, NA's and "" in merges

I understand that NA's in character vectors are displayed differently than NA's in factor vectors. > c("x", NA, "y") [1] "x" NA "y" > as.factor(c("x", NA, "y")) [1] x <NA> y Levels: x y That seems sensible enough. But shouldn't I see the same behavior in a dataframe? > test <- data.frame(a =

Thanks to Brian Ripley, Gregory Warnes, and Dennis Murphy for considering my problem about "NA" in character strings. The nub of the issue seems to be that you can not have a string with "NA" in it in a character vector in R without it being intrepreted as meaning NA (i.e., not available). The only work-arounds involve renames of various sorts. Perhaps this is more appropriate

Hello, R-devel! I posted to R-help, and (inappropriately) to R-bugs, this R/S-Plus difference: > LETTERS[c(NA,2)] in S is c("","B"), but in R is c("NA","B") Kurt Hornik <Kurt.Hornik@ci.tuwien.ac.at> wrote: > I think we do not want to change this. ... > R> is.na(LETTERS[c(NA,2)]) [1] TRUE FALSE > so we really have NA but it is

Hi, all, I've been converting code from S-Plus ("S" for short) to R for a few weeks. Here are some differences I've found, aside from the big well-known ones (scoping, models, data storage) and the contents of Kurt Hornik's FAQ section 3.3.3. Let me start with the ones that seem like serious bugs or deficiencies: 1) LETTERS[c(NA,2)] in S is

Hi, all, I've been converting code from S-Plus ("S" for short) to R for a few weeks. Here are some differences I've found, aside from the big well-known ones (scoping, models, data storage) and the contents of Kurt Hornik's FAQ section 3.3.3. Let me start with the ones that seem like serious bugs or deficiencies: 1) LETTERS[c(NA,2)] in S is

Hi, I often have large dataframes with many variables and many NA's, from which I would like to subset out some rows. Here is a toy example: > x <- data.frame(a = c("x", "y", "z"), b = c(1, NA, 5)) > x a b 1 x 1 2 y NA 3 z 5 I realize that, if I know the values in x$b that I want to subset, things are easy: > x[x$b %in% c(1),] a b 1 x 1

Hi, In 1.4.1, I was able to create extra "empty" rows in a dataframe as so: > x <- data.frame(a = letters[1:3], b = 1:3) > x a b 1 a 1 2 b 2 3 c 3 > x[4,] a b NA NA NA > rbind(x, x[4,]) a b 1 a 1 2 b 2 3 c 3 NA NA NA > R.version _ platform sparc-sun-solaris2.6 arch sparc os solaris2.6

Typically, when I use strptime with "impossible" dates I get an NA, which is what I expect. > version _ platform sparc-sun-solaris2.6 arch sparc os solaris2.6 system sparc, solaris2.6 status major 1 minor 3.0 year 2001 month 06

Hi, I think that there is something that I am misunderstanding in creating tables using dates that are of class POSIXct. Consider: > x <- data.frame(date = as.POSIXct(strptime(c(rep("2002-10-17", 4), rep("1999-12-08", 2)), format = "%Y-%m-%d"))) > x date 1 2002-10-17 2 2002-10-17 3 2002-10-17 4 2002-10-17 5 1999-12-08 6 1999-12-08 > table(x$date)

Almost all of the heavy crunching I do in R is like: > for(i in long.list){ + do.something(i) + } > collect.results() Since all the invocations of do.something are independent of one another, there is no reason that I can't run them in parallel. Since my machine has four processors, a natural way to do this is to divide up long.list into 4 pieces and then start 4 jobs, each of which

In previous versions of R (at least in 1.5.1, I think), my practice was not to include an INDEX file in the package. R CMD check did not complain and an INDEX was created for me when I use R CMD build. At least, this is how I remember it. I thought that this was a good way to behave since it ensured that my INDEX was automatically kept up to date by R, without me having to worry about what

Hi, all, I've been converting code from S-Plus ("S" for short) to R for a few weeks. Here are some differences I've found, aside from the big well-known ones (scoping, models, data storage) and the contents of Kurt Hornik's FAQ section 3.3.3. Let me start with the ones that seem like serious bugs or deficiencies: 1) LETTERS[c(NA,2)] in S is

This seemed too advanced for r-help and is related to the recent discussion of character vectors in dataframes. Following Brian Ripley's most excellent advice, we are moving to a world in which character vectors in dataframes are always of class AsIs. The cool way of doing this seemed to be the following: > cat(c("x", "y", "z"), file = "test.txt",

I am not sure if this is a bug within is.na<- or if it lies deeper in the dataframe construction process. Indeed, perhaps it is not a bug at all (in which case I would suggest that the help page for NA be provided with a warning for unsuspecting users (like me)). When used on a character vector within a dataframe, is.na<- coerces the vector to factor. > x <- data.frame(var =

We are performming a series of S+ 6.0 versus R 1.3 comparisons. (If anyone has already written scripts for this purpose, we would be eager for a copy.) The purpose is to see if there are any "gotchas" -- places were S+ works and R doesn't -- that would prevent us from going all the way over to R. (We have lots of legacy code, so the conversion costs are non-trivial.) As part of this

Also in assign() there some arguments lacking in R such as 'frame' and 'where', though I guess that 'frame' in S may be similar to 'pos' in R. Harvey -----Original Message----- From: David Brahm [SMTP:a215020@agate.fmr.com] Sent: Wednesday, October 03, 2001 11:36 AM To: r-help@stat.math.ethz.ch Cc: Kurt.Hornik@ci.tuwien.ac.at; r-bugs@r-project.org Subject:

Environment variables set with Sys.putenv() disappear (i.e. become "") after a while, especially after heavy-duty I/O. Example: R> x <- matrix(1., 3000, 3000) R> save(x, file="myx.RData") R> Sys.putenv(HOME="/tmp") R> while (Sys.getenv("HOME") != "") {cat("ok\n"); load("myx.RData")} The loop prints

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

The inconsistency is that you use $<- to set the column, then [[<- to change it. Had you tried to set the column by x[[1]] <- as.character(x[[1]]) you would have seen the problem immediately (it does not work as you would have intended). If you want to be sure to turn off conversion to factor, you need to set the column to class "AsIs". My belief is that will behave

Hey everyone! I am seeing strange behavior with NA in the rownames of dataframes: > a <- data.frame(1:3, row.names = c("r1", NA, "r3")) > cbind(a) X1.3 r1 1 <NA> 2 r3 3 Everything works. The peculiar thing is that when the NA is in the first row, things no longer work as I would have expected: > b <- data.frame(1:3, row.names