similar to: Another problem with next method

Dear R developers, It would be great if you could implement the two minor code changes suggested below, which would help processing large objects in R. Jens Oehlschl?gel # Wish no. 1: let [.AsIs return the class AFTER subsetting, not the class of the original object # Wish no. 2: adjust write.csv and write.csv2 for multiple calls in chunked writing # Rationale no. 1: a couple of packages

? Fri, 12 Jul 2024 17:35:19 +0200 Hilmar Berger via R-devel <r-devel at r-project.org> ?????: > This can be finally traced to base::rank() (called from > xtfrm.default), where I found that > > "NB: rank is not itself generic but xtfrm is, and rank(xtfrm(x), ....) > will have the desired result if there is a xtfrm method. Otherwise, > rank will make use of ==, >,

Hi, although I've done S3 dispatching for more than a decade now, I think I managed to overlook/avoid the following pitfall when using NextMethod(): If you explicitly pass argument '...' to NextMethod(), you will effectively pass those argument twice to the "next" method! EXAMPLE: foo0 <- function(...) UseMethod("foo0"); foo1 <- function(...)

>> One clear moral seems to be don't do anything more inside a >> generic function than you really need to do. Keep it *very* >> simple indeed. >> > I recall JMC saying something like, all generic functions > should be one line long; a call to the appropriate UseMethod. It certainly is encouraging to know that others also have been confused by aspects of

My question is when the object argument of NexthMethod be used? In the following example, weather object argument is used will not affects the result. ### foo=function(x) {UseMethod("foo")} foo.cls1=function(x) { x=x+1;class(x)<-"ncls" NextMethod() } foo.ncls=function(x) { cat("ncls\n") } foo.cls2=function(x) { cat("cls2\n");print(x) }

Hi all, I'd like to ask if the following behavior is a bug. To me it certainly feels surprising, at the very least. In this example, I would like to call NextMethod() from my `child` object, have `cols` be left untouched, and then substitute(cols) in the parent method. It works when you use a `parent` object (as expected), but I would have also expected to get `mpg` back when calling it from

Hello,   ###  I created two classes "A" and "B". "A" is the superclass of "B".   setClass("A", representation(s1="numeric"),prototype=prototype(s1=8)) setClass("B",contains="A",representation(s2="character"),prototype=list(s2="hi")) myA=new("A") myB=new("B")   ####  I created

S Programming by Venables and Ripley (page 78) has the example listed at the end of this email. However, I get the following error when I try the example. I don't understand the descriptions of NextMethod on its help page. Could somebody let me know how to fix the error of this example? > test(x) c1 c2 Error in NextMethod() : no method to invoke Calls: test -> test.c1 -> NextMethod

Good evening, I recently have observed slow merges when combining multiple data frames derived from DataFrame and base::data.frame. I observed that the index column of intermediate tables was of class <AsIs> (automatically converted from character). The problem occurred mainly when using the sorted = T option in base::merge. This can be traced to xtfrm.AsIs being more than 100 times slower

Hi, I'm new to OOP in R so please forgive the naiveness of some of the questions. Here are a couple of them. It would be great if you can contrast to OOP in Java. 1. R's S4 appears to centered around a dispatch mechanism which in my understanding is just a way to implement polymorphism. Now, here's the snag, I thought polymorphism was an aspect of OOP not by itself the definition of

Dear, I'm looking for some examples on OO programming in R. I have the programming manual with explanation on UseMethod and NextMethod but I miss some practical examples to get me going (I hope). I searched the web but could not find a good independent tutorial on this. Any suggestions are welcome, Kris -- ------------------------------------------------------------------------

I'd like to have a class A that computes a likelihood, and a subclass B that computes the same likelihood by sometimes throws in an additional term (B includes measurement error). So B's likelihood needs to call A's, and then (sometimes) multiply by an additional term. It sounds as if, in the S3 scheme, NextMethod is supposed to do this: like.A <- function(stuff) compute value

Thanks John. ?boxcox says: ************************* Arguments object a formula or fitted model object. Currently only lm and aov objects are handled. ************************* I read that as saying that boxcox(lm(z+1 ~ 1),...) should run without error. But it didn't. And perhaps here's why: BoxCoxLambda <- function(z){ b <- MASS:::boxcox.lm(lm(z+1 ~ 1), lambda = seq(-5, 5,

Hi Bert, On 2023-07-08 3:42 p.m., Bert Gunter wrote: > Caution: This email may have originated from outside the organization. Please exercise additional caution with any links and attachments. > > > Thanks John. > > ?boxcox says: > > ************************* > Arguments > > object > > a formula or fitted model object. Currently only lm and aov objects

Dear list members, After further testing, I found that the following simplified version of model.matrix.lme(), which omits passing xlev to the default method, is more robust. The previous version generated spurious warnings in some circumstances. model.matrix.lme <- function(object, ...){ data <- object$data if (is.null(data)){ NextMethod(formula(object),

R : Copyright 2001, The R Development Core Team Version 1.3.1 (2001-08-31) > tmp <- factor(1:3) > get("print.factor")(tmp) [1] 1 2 3 Levels: 1 2 3 > print.a <- function(x,...) { + print("this is a") + NextMethod("print", x, quote = FALSE, right = TRUE, ...) + } > > get("print.a") function(x,...) { print("this is a")

Hi, The 2 man pages give inconsistent description of class(): Found in ?class: If the object does not have a class attribute, it has an implicit class, ?"matrix"?, ?"array"? or the result of ?mode(x)? (except that integer vectors have implicit class ?"integer"?). Found in ?UseMethod: Matrices and arrays have class ?"matrix"?

Short example: > str(d <- data.frame(a = I(letters[1:5]))) `data.frame': 5 obs. of 1 variable: $ a:Class 'AsIs' chr [1:5] "a" "b" "c" "d" ... > str(d[TRUE,,drop = FALSE]) `data.frame': 5 obs. of 1 variable: $ a: chr "a" "b" "c" "d" ... The real problem about this is, that as soon

Can someone help me understand the following behavior of "[<-" ? If I define a simple class based on a matrix, the [<- operation only inserts into the first column: > x <- matrix(rnorm(10),nrow=5,ncol=2) > class(x) <- "foo" > "[<-.foo" <- function(x, i, j, value) { + if(missing(i)) i <- 1:nrow(x) + if(missing(j)) j <-

On Tue, 14 May 2019 at 12:31, Pavel Krivitsky <pavel at uow.edu.au> wrote: > > > Note that disabling name-based dispatch implies two things: 1) the > > inability to override your method by defining gen.formula in the > > global environment, and 2) another package can break yours (i.e., > > internal calls to gen()) by registering an S3 method for gen() after >