Displaying 20 results from an estimated 20000 matches similar to: "Odd outcome of attr with environments (PR#2148)"
2001 Apr 11
5
replicating lists
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
2000 Mar 22
3
segmentation fault with 1D array (PR#500)
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 =
2002 Jan 04
2
Problem with "missing" in "local" (PR#1241)
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
2002 Nov 22
4
Small change to plot.xy
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)
2000 Feb 01
2
Segmentation fault in recursion, 0.90.1 (PR#409)
The following gives an immediate segmentation fault, v 0.90.1
"fred" <- function(x) { print(x); Recall(x-1)}
fred(0) # segmentation fault at recursion 831
Obviously this recursion is non-terminating, but shouldn't it be caught
and reported at some limit? In 0.64.1 we had
Error: protect(): stack overflow
at recursion 831. Cheers, Jonathan.
Jonathan Rougier
2000 May 19
7
variance of a scalar (PR#546)
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,
1999 Feb 17
1
dim enquiry
This is a minor question, but is there any difference between the two
objects
fred <- structure(1:10, dim = c(2,5))
and
fred <- structure(1:10, .Dim = c(2,5))
Should I be using one rather than the other? Thanks, Jonathan.
Jonathan Rougier Science Laboratories
Department of Mathematical Sciences South Road
University of Durham Durham DH1 3LE
1999 Jan 14
1
libraries
Am I right in thinking that there a discrepancy between the ?library
documentation and the library() function? If I have a library called
"patches", then according to the documentation (0.62.4) patches/R should
contain source files like fred.R and george.R, but in practice the library
only loads if both fred.R and george.R are given in a file called patches
in the R subdirectory of
1999 Aug 18
2
diag()
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 +
2002 Aug 20
1
NA and help page for "&" and "|"
Hi everyone,
Can I suggest an addition to the help page for logical AND and OR,
indicating the behaviour of NA (which is currently not mentioned at
all). I think something simple like an extra paragraph in Details, eg
\code{NA} is a valid logical object. Where a component of \code{x} or
\code{y} is \code{NA}, the result will be \code{NA} if the outcome is
ambiguous. In other words \code{NA
1999 Nov 04
2
New codes() methods
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)
2001 Jan 09
3
Inconsistent behaviour in solve (PR#805)
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
2000 Oct 16
2
print problem with data frames (PR#698)
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
2002 Oct 08
3
hash argument of new.env()
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
1999 Oct 08
1
dimnames and subscripting (PR#293)
I am not sure that this is a bug, but it was unexpected -- of course my
expectations are fallible, eg column ordering in model.matrix()! When an
array is subscripted the names of the dimnames list are lost (v 64.1).
fred <- array(1:12, 2:4, list(A = letters[1:2], B = letters[3:5], C =
letters[6:9]))
dimnames(fred)
dimnames(fred[1, , ])
dimnames(fred[1, , , drop=FALSE])
In the first
1999 Feb 10
1
Function parsing (PR#118)
Is anyone else concerned with the way in which the R function parser
relocates comments that occur after condional expressions in functions to
before, i.e.
fred <- function(x) {
# wonder what x is like
if (x>0) stop("Sorry non-positive x only")
# that showed x big-time!
x
}
but then fred is parsed and stored as
"fred" <-
function (x)
{
# wonder what x is
1999 Oct 26
1
dodgy list operation (PR#298)
I can generate a segmentation fault as follows, where I would expect a
syntax error:
fred <- as.list(1:10)
lapply(fred, "[[")
platform sparc-sun-solaris2.5.1
arch sparc
os solaris2.5.1
system sparc, solaris2.5.1
status
status.rev 0
major 0
minor 64.1
1999 Aug 25
2
Error in ?text (PR#256)
Just a minor point, but the adj argument in ?text is described wrongly
(0.64.1). Perhaps the following might be added to the details.
Values of 0, 0.5, and 1 specify left/top, middle and right/bottom,
respectively. The default is for centred text, ie \code{adj = c(0.5,
0.5)}.
Cheers, Jonathan.
Jonathan Rougier Science Laboratories
Department of
2000 Apr 06
2
Strange behaviour of image (PR#510)
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,
1999 Mar 10
2
.Alias and memory
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,