Displaying 20 results from an estimated 9000 matches similar to: "Something strange in "?assign"? (PR#433)"
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
2001 Apr 11
0
replicating lists (fwd) (PR#907)
Filed as a bug, as suggested by Brian R., Jonathan.
Jonathan Rougier Science Laboratories
Department of Mathematical Sciences South Road
University of Durham Durham DH1 3LE
tel: +44 (0)191 374 2361, fax: +44 (0)191 374 7388
http://www.maths.dur.ac.uk/stats/people/jcr/jcr.html
---------- Forwarded message ----------
Date: Wed, 11 Apr 2001 09:15:26 +0100
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)
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
2002 Feb 20
1
Pivoting in chol
Hi Everyone,
I have modified my version of R-1.4.1 to include choleski with pivoting
(like in Splus). I thought R-core might consider including this in the
next version of R, so I give below the steps required to facilitate
this.
1. Copied Linpack routine "dchdc.f" into src/appl
2. Inserted line F77_SUBROUTINE(dchdc) in src/appl/ROUTINES
3. Inserted "dchdc.f" into
2000 Nov 10
1
Modification to cov and cor
Can I suggest that in cov and cor the lines
if (is.data.frame(x))
x <- as.matrix(x)
if (is.data.frame(y))
y <- as.matrix(y)
be replaced by
if (is.data.frame(x))
x <- data.matrix(x) # coerce logical and factors
if (is.data.frame(y))
y <- data.matrix(y) # likewise
This would allow things like
> data(iris)
> cor(iris)
which
2002 Mar 15
1
Thought on crossprod
Hi everyone,
I do a lot of work with large variance matrices, and I like to use
"crossprod" for speed and to keep everything symmetric, i.e. I often
compute "crossprod(Q %*% t(A))" for "A %*% Sigma %*% t(A)", where
"Sigma" decomposes as "t(Q) %*% Q". I notice in the code that
"crossprod", current definition
> crossprod
function (x,
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
2000 Sep 07
1
.C and DUP=TRUE versus .Call
Hi Everyone,
I have a piece of C code that uses R_alloc, and so I set DUP=TRUE in the
call using ".C". As I understand it this takes a copy of each object
passed to my function. If these objects are large then this could be
expensive. My question is, if I rewrote the code to use .Call, would I
avoid this duplication by using the objects themselves (they are not
modified in the code)
2000 Mar 01
1
"is.qr" definition (PR#465)
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
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
2001 Nov 13
1
Small change to "cut.default"
Hi everyone,
Can I suggest the following cosmetic change to cut.default (R-1.3.1), to
adjust the labels in the case that include.lowest = TRUE:
arrow:dma0jcr% diff -u cut.R my.cut.R
--- cut.R Tue Nov 13 12:28:35 2001
+++ my.cut.R Tue Nov 13 12:35:16 2001
@@ -25,6 +25,11 @@
ch.br[-nb], ",", ch.br[-1],
if(right)"]"
2002 Oct 22
0
methods function
Hi everyone,
I've noticed that the methods function is incomplete. The obvious
example is if I write a function "$.foo", it is not picked up by
methods:
> "$.foo" <- function(object, name) get(name, envir=object[[1]])
> "$<-.foo" <- function(object, name, value) {assign(name, value, envir=object[[1]]); object}
> happy <-
2001 Jun 11
1
Additional output in cancor
Hi everyone,
Can I suggest an additional output component in cancor, from package
mva? It would be useful to have the number of canonical correlation
vectors, equivalently the rank of the covariance between x and y (label
"rank"). This would usually be min(dx, dy), where dx and dy have
already been computed for the svd function, but there might be
situations where it was less than
2001 Mar 29
1
Detaching "ctest"
Hi Everyone,
We have just upgraded to R-1.2.1, and I note, in contrast to R-1.1.1, that
ctest is now loaded automatically. The mechanism for this is to create a
.First function in base:
.First <- function() {
require("ctest", quietly=TRUE)
}
Now I don't want ctest, but I find that simply putting
if (length(grep("ctest", search())))
detach(package:ctest)
into
2000 Dec 07
0
Tuning the nlm function
Hi Everyone,
Is there a simple way to force nlm to take larger initial steps? Setting
print.level = 2 allows me to inspect the step size at each iteration, but
I appear not to have made any appreciable impact on it by changing values
of typsize, fscale, steptol or stepmax. The steps repeatedly come out
tiny, 1e-9 typically, and the algorithm is terminating not because the
gradient is zero (it
2001 Mar 21
0
Suggest new outer for R-1.3
Hi everyone,
Can I suggest the following modification of outer for R-1.3, in the
interests of speed and size of calculation:
*******************************************************************
"outer" <-
function (X, Y, FUN = "*", ...)
{
no.nx <- is.null(nx <- dimnames(X <- as.array(X)))
dX <- dim(X)
no.ny <- is.null(ny <- dimnames(Y <-
2002 May 16
0
Re: [R] NaN/NA and sprintf double format (PR#1561)
ripley@stats.ox.ac.uk wrote:
>
> On Tue, 14 May 2002, Dirk Eddelbuettel wrote:
>
> > With a (late prerelease of) 1.5.0 on Windows, using sprintf on NaN
> > yields garbage when the number of decimal is specified while it
> > works fine for NA:
> >
> > > sprintf("%.2f", NA)
> > [1] "0.00"
>
> I get that on Linux too, but
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 +
2005 Oct 31
1
[R] unvectorized option for outer()
> From: Thomas Lumley
>
> On Sun, 30 Oct 2005, Jonathan Rougier wrote:
>
> > I'm not sure about this. Perhaps I am a dinosaur, but my feeling is
> > that if people are writing functions in R that might be subject to
> > simple operations like outer products, then they ought to be writing
> > vectorised functions!
>
> I would agree. How about an