similar to: Cautionary tale about c (PR#695)

Here is a cautionary tale to help others avoid my folly! I kept running into bizarre problems with my rails app. I run the latest Rails with FastCGI, Oracle 10g and Apache 1.x. After moderate load the server would throw up application errors. Looking in the logs I noticed that my underlying Oracle DB was complaining that it had opened too many processes and won''t open any more. Hmm...

Hello, We recently undertook to migrate our domain from samba-TNG to samba-2.2.2. However, it did not go smoothly. One of the main reasons is that even if you start 2.2.2 with the domain SID from the TNG installation, you find that the users' RIDs are different. This is because samba-TNG calculates the RID from the unix UID using the formula UID*4 + 1000 where as 2.2.2 uses UID*2 +1000. At

I'm mainly writing this in hopes that it gets picked up by Google in case anyone else runs into this problem. I was going to distribute the source & binaries for the first sneaky- peek at Swfdec for Mac OS X today. But yesterday, when I tried running my player application within Mac OS X's PowerPC emulator (Rosetta), I noticed it was crashing in some animations with the

I was surprised to find that the variance of a scalar, using var(), is NA. Surely this should be zero? Cheers, Jonathan. --please do not edit the information below-- Version: platform = sparc-sun-solaris2.7 arch = sparc os = solaris2.7 system = sparc, solaris2.7 status = Patched major = 0 minor = 99.0 year = 2000 month = February day = 9 language = R Search Path: .GlobalEnv,

I find this a bit puzzling ... > solve(matrix(c(5, 2, 3, 1), 2, 2), c(Inf, 3)) [1] NaN Inf > solve(matrix(c(5, 2, 3, 1), 2, 2)) %*% c(Inf, 3) [,1] [1,] -Inf [2,] Inf I would expect the answer to be c(-Inf, Inf), so why has the -Inf been replaced by NaN in solve? Cheers, Jonathan. --please do not edit the information below-- Version: platform = sparc-sun-solaris2.7 arch = sparc

Here's a nasty one. The following has caused a segmentation fault and possibly also a bus error. fred <- 1:6 dim(fred) <- 6 dimnames(fred) <- list(LETTERS[1:6]) mm <- matrix(1:12, 2, 6) mm %*% fred # segmentation fault here In the case without the dimnames assignment the result is OK. Cheers, Jonathan. --please do not edit the information below-- Version: platform =

The following commands z <- matrix(seq(0, 1, len=1000)) image(z, 1, z, zlim=c(0, 1), col=gray(1:10/10)) appear to violate the image functionality as described on the help page. As I understand it, by specifying a zlim of c(0, 1) and a colour vector of length 10, the colours should correspond to the intervals (0, 0.1), (0.1, 0.2), ..., (0.9, 1.0), this being 10 equally-spaced intervals on (0,

Might it be possible to tighten the definition of "is.qr". I noticed that after I mistakenly typed example(lm) # make lm object named lm.D9 qr.Q(lm.D9) which exhausted the heap memory and produced two warning messages. As an object of class "lm" has a "qr" component, "is.qr" failed to detect that "lm.D9" was not a "qr" object. The

I'm just back from a computer practical where we ran into > "f" <- function(x) 2(x^2) # for 2 * x^2 This definition was taken as legitimate, although using the function generated the error message > f(3) Error in f(3) : attempt to apply non-function Am I right in thinking that in prevous versions of R this definition would have been declared as a syntax error? Surely a

Hi Everyone, The following rather extreme claim on memory causes a segmentation fault on my installation: fred <- matrix(1:1200, 20, 60) littleOP <- function(x, y) { z <- as.vector(x) %*% t(as.vector(y)) dim(z) <- c(dim(x), dim(y)) z } littleOP(fred, fred) # this is OK littleOP(littleOP(fred, fred), fred) # whoops! Segmentation fault What's a bit strange

The following seems to be odd behaviour: fred <- 1:10 mode(fred) # "numeric" exists("fred") # TRUE exists("fred", mode="numeric") # FALSE Unless I have misunderstood, the final evaluation should be TRUE, as an object called "fred" exists and its mode is "numeric". In the same category, I have just noticed that get("fred")

I get a segmentation fault as follows: > tmp <- array(list(), c(3, 4)) > tmp[[1, 2]] NULL # as expected > tmp[[1, 2]]$fred <- 1:10 > tmp # as expected [,1] [,2] [,3] [,4] [1,] "NULL" "List,1" "NULL" "NULL" [2,] "NULL" "NULL"

Another one from the student computer practicals: it is possible to create a dataframe that cannot be printed. Thus > fred <- data.frame(happy=c(TRUE, FALSE, TRUE), sad=7:9) > tmp <- fred[c(FALSE, FALSE, TRUE, TRUE)] # no error message! > tmp Error in as.matrix.data.frame(x) : dim<- length of dims do not match the length of object > print.default(tmp) $"NA" NULL

Hi everyone, Is there any reason why we should not automatically coerce a factor supplied as an argument to col in a plotting function? The following modification (to R-1.6.1) seems pretty harmless > plot.xy function (xy, type, pch = 1, lty = "solid", col = par("fg"), bg = NA, cex = 1, ...) { if (is.factor(col)) col <- codes(col)

Hi Everyone, At the moment it is not possible to replicate complex lists, but only simple ones: > rep(list(fred = 1:10), 10) # works fine > rep(list(fred = 1:10, happy = "squash"), 10) Error in rep(list(fred = 1:10, happy = "squash"), 10) : Unimplemented feature in rep There is nothing in ?rep that suggests that the latter should not work, and I think it would

I would like to suggest a slight modification to diag(). In the case where x is a matrix with both row names and column names the same, it would be reasonable if the resulting vector also had those names. I often use diag() on variance matrices, where this modification is helpful. The modification requires replacing if (is.matrix(x) && nargs() == 1) return(c(x)[1 +

Hi everyone, There is no mention in ?new.env (R-1.6.0) of what the effect of setting the hash argument of new.env() actually does. What does it mean in performance terms to say that "the environment will be hashed"? Thanks, Jonathan. -- Jonathan Rougier Science Laboratories Department of Mathematical Sciences South Road University of Durham

Hi Everyone, Can I suggest a couple of new `codes' methods. I know codes is a bit dodgy (at least, according to the comments in codes.factor), but for what it's worth I like to extract codes from data frames of factors, for which the following two functions (which operate recursively) are helpful: "codes.default" <- function(x) { if (is.list(x)) lapply(x, codes)

In an effort to encapsulate my dependence on class in order to deal with oldclass/class in Splus I defined the functions tfclass <- class "tfclass<-" <- function(x, value){ class(x) <- value ; x } and also the function classed <- function(x, cls) {class(x) <- cls; x} This last allows me to end a function definition with ... classed(somecalc,

Hi everyone, I encountered unexpected behaviour when calling "missing" within a "local" environment, namely fred <- function(x, y) { x <- as.vector(x) local({ dontwantme <- 1:100 if (missing(y)) print("No \"y\" today") }) x } whereupon I get > fred(1:10) Error in eval(expr, envir, enclos) : "missing" illegal use of