similar to: Modification to cov and cor

Displaying 20 results from an estimated 10000 matches similar to: "Modification to cov and cor"

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)
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
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 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 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
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 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 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 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)"]"
2000 Feb 11
1
Something strange in "?assign"? (PR#433)
According to the assign helpfile (0.90.1) the "assign" function is function (x, value, pos = -1, envir = sys.frame(sys.parent()), inherits = FALSE, immediate = TRUE) which is not quite the implementation, which is function (x, value, pos = -1, envir = pos.to.env(pos), inherits = FALSE, immediate = TRUE) This seems to have the following interesting effect. "short.fun"
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
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 <-
2007 Dec 03
1
cor(data.frame) infelicities
In using cor(data.frame), it is annoying that you have to explicitly filter out non-numeric columns, and when you don't, the error message is misleading: > cor(iris) Error in cor(iris) : missing observations in cov/cor In addition: Warning message: In cor(iris) : NAs introduced by coercion It would be nicer if stats:::cor() did the equivalent *itself* of the following for a data.frame:
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