similar to: Testing for S4 objects

Dear list members, I'm encountering the following problem with package dependencies and imports: The Rcmdr package doesn't declare a formal dependency (via depends or suggests in the package DESCRIPTION) on the rgl package because the latter apparently causes problems on some systems. This allows the Rcmdr package to build and check on systems without rgl present; if rgl isn't

When passing a list as an argument to a function, I find it convenient to attach it in the first line of th function code, then refer to the components as A, B, etc. rather than as list$A, list$B, etc. If I pass a S4 class object, is there a way to "attach" it, or do I have to refer to the slots as object at A, objetc at B, etc.? I could always make copies, A <- object at A

Hi the list, With basic type, length gives the length of the vector Wtih list, length gives the number of item With S4 object, length gives...one. Even with an objet with empty slot. setClass("E",representation(e="numeric")) [1] "E" length(new("E")) [1] 1 setClass("E",representation(e="matrix")) [1] "E"

Hi, I created a class (S4) with some slots like value, date, description (it's actually a financial transaction class). Now I need a method to convert this class forth and back into a single row data.frame, where every slots represents a column. This method looks at the moment like this: > setMethod("as.data.frame", "Transaction", function(x, row.names =

I looked through the documentation and the mailing lists and could not find an answer to this. My apologies if it has already been answered. If it has, a pointer to the relevant discussion would be greatly appreciated. Creating S4 classes containing environments exhibits unexpected behavior/features.? These have a different in two ways: 1) slotName for the data: ".xData" instead of

Hello, an S4 class "Foo" is defined with a setter, $. For several reasons, the setter calls a function, .foo.update(). However, bypassing the argument names of the setter does not work. Question 1: Why not and how can I fix this? Question 2: What is the way to define either the function or the setter to modify the original object (not returning the modified copy of it an overwrite the

Dear Roman, I've attached the latex file for the copy-edited version of your manuscript -- correcting English grammar and style, and making the paper conform more closely to the R News style. Can you check this over to confirm that I've not altered the meaning of your text and to approve the copy-edits? Thanks, John -------------------------------- John Fox Department of Sociology

Dear R-help list members, I forgot to copy my reply to the r-help list. Here's most of it. John -------------------------------- John Fox Department of Sociology McMaster University Hamilton, Ontario Canada L8S 4M4 905-525-9140x23604 http://socserv.mcmaster.ca/jfox -------------------------------- -----Original Message----- From: John Fox [mailto:jfox at mcmaster.ca] Sent: Sunday,

I have been retooling an S4 class definition to include another slot and have found that the methods::validObject function (defined in methods/R/SClasses.R) in R-devel throws an error that isn't caught internally (and thus not controllable by 'test' argument) when retrieving a non-existent slot. The offending line of code is shown below: > validObject function (object, test =

Dear Developers, In current implementation of validity method, objects are first coerced to superclass (slots are striped). Thus, it is not possible to write validity method which would perform some checks on children slots. Say, I want to check if number of slots in a class is equal to "n": setClass("A", representation(a="numeric", n="integer"),

Dear r-devel list members, I've prepared a version of the Rcmdr package that uses the new tools for internationalization and localization in R 2.1.x. For the present, this is the development version of the Rcmdr package (1.1-0), available at <http://socserv.socsci.mcmaster.ca/jfox/Misc/Rcmdr/index.html>. There is currently a French translation provided with the package, courtesy of

Dear R-devel list members, For several years, I've maintained for my private use and for demonstrations a set of functions [e.g., for indexing, with(), summary(), etc.] that employ the RODBC package and a database to provide a "pseudo" data frame. Row "indexes" can be specified as SQL queries. I know that the idea isn't original, and I haven't done anything with

Dear list members, I've just uploaded version 1.0-0 of the Rcmdr package to CRAN. For people who haven't seen the package before, the "R Commander" provides a basic-statistics graphical user interface to R, based on the tcltk package. The new version incorporates a number of improvements to the R Commander interface, as documented in the CHANGES file distributed with the

Dear list members, I've just uploaded version 1.0-0 of the Rcmdr package to CRAN. For people who haven't seen the package before, the "R Commander" provides a basic-statistics graphical user interface to R, based on the tcltk package. The new version incorporates a number of improvements to the R Commander interface, as documented in the CHANGES file distributed with the

Hi All, I have tried to find an answer within documentation, but I cannot: o How can call a class "slot" without knowing the name a priori? E.g., let's say I use the "pcaMethods" library to create a "pcaRes" object. How can I call parts of that object without using the specific names of the object in the call? example code: library(pcaMethods)

I want to loop through slots of an S4 object and am unsure how to do so since the only way I can find to access them is individually in the form 'object@slotName'. I have guessed at a few possibilities which did not work and I have read some S4 object tutorials and things but still unsuccessful. I presume it is possible though? Any help would be much appreciated, Scott [[alternative

Hi all, I'm working with the S4-Class system and I have a little problem with Implementing iteration functionality in my S4 class but it don't work: > setClass("foo",representation(bar="list")) > x <- new("foo",bar=list(1,2,3)) >for(e in x) cat(e) invalid type/length (S4/1) in vector allocation But when I extend from a

Dear list members, In re-running with GLMM() from the lme4 package a generalized-linear mixed model that I had previously fit with glmmPQL() from MASS, I'm getting a warning of a convergence failure, even when I set the method argument of GLMM() to "PQL": > bang.mod.1 <- glmmPQL(contraception ~ as.factor(children) + cage + urban, + random=~as.factor(children) + cage +

Hey everyone, I would like to develop a package using S4 classes. I have to define several S4 classes that inherits from each others as follow: # A <- B <- C <- D I also would like to define .DollarNames methods for these class so, if I have understood well, I also have to define an old class as follow: # AOld <- A <- B <- C <- D setOldClass(Classes = "AOld")

Two recent changes have been committed to r-devel, related to discussions on this list earlier: 1. setOldClass() has an argument prototype= to specify the default object for the class. If provided, the S3 class can be a slot in an S4 class, with a valid default object. (It's still not going to work well to have an S3 non-virtual class as a superclass of an S4 class. See the