similar to: S4 class, passing argument names to function, modify original

I feel tedious when I define a S4 class and the methods. For each method, I have to call both setMethod and setGeneric (or both setReplaceMethod and setGeneric). I would like a more compact grammar so that I can reduce the key strokes. I'm wondering if there is a better way available. setClass( Class='A', representation=representation( x='numeric' )

Hi R friends,   I'm still studying S4 classes and I have a question about slot assignment. Why would I have to use a special setter method [example 2 below] if I can assign data to a slot directly when I call new() [example 1 below]?   ## first way to do it (the idiosyncratic way?) setClass(Class = "TestClass", representation = representation(myDf = "data.frame"))

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

Hi I have some problems in defining new generic functions and classes. Just have a look at the following example: require(fPortfolio) setClass("PROBECLASS", representation( type="character" ) ) isGeneric("setType<-") #Returns TRUE #I would like to define a specific function for

Hi I have some problems in defining new generic functions and classes. Just have a look at the following example: require(fPortfolio) setClass("PROBECLASS", representation( type="character" ) ) isGeneric("setType<-") #Returns TRUE #I would like to define a specific function for

Dear R users! Several languages like C# or VB allow one to create properties; typically these are under 'get', 'set' tags. My question is this really, what are similar or comparable strategies in R, and what might be preferred? I have a couple of situations where I want a certain computation to belong to a class, but I do not really want to seperate it out to a stand-alone

Dear r-help list members, Is there a way to test whether an object is an S4 object? The best that I've been able to come up with is isS4object <- function(object) !(is.null(slotNames(object))) which assumes that an S4 object has at least one slot. I think this is safe, but perhaps I'm missing something. Thanks, John -------------------------------- John Fox Department of

Dear r-help list members, Is there a way to test whether an object is an S4 object? The best that I've been able to come up with is isS4object <- function(object) !(is.null(slotNames(object))) which assumes that an S4 object has at least one slot. I think this is safe, but perhaps I'm missing something. Thanks, John -------------------------------- John Fox Department of

List, In order to get rid of some old, unreadable S3 code in package sp, I'm trying to rewrite things using S4 methods. Somewhere I fail, and I cannot sort out why. In order to isolate the problem, I created two functions, doNothing<- and dosth, and both should do nothing. The issue is that in most cases they do nothing, but in some cases dosth(obj) changes the class of obj and breaks with

Dear all, Assume that I have an S4 class "MyClass" with a slot "myname", which is initialized to: myname="" in method("initialize"): myclass <- new("MyClass", myname="") Assume that class "MyClass" has a method "mymethod": "mymethod.MyClass" <- function(object, myname=character(0), ...) {

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"),

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)

Hi the list, I try to use callNextMethod in a setteur ([<-) but it does not work. Any raison ? Any other option ? --- 8< ------------------ ### Class B0 ### setClass("B0" , representation(b0 = "numeric")) setReplaceMethod("[","B0",function(x,i,j,value){x at b0 <- -value}) a <- new("B0") a at b0 <- 3 a a["b0"] <- 3 a

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 I have the code like I show below. The problem here is that I have a setReplacementMethod to set the value of my class slot. However, this function doesn't work when I call it within another function definition (declared by setMethod) of the same class. I do not understand this behavior that much. I'm wondering how to make this work? Any help would be really appreciated. Thank you.

Hi, I recognized that the function 'setReplaceMethod' is creating a character vector in the user workspace having the name (e.g. "newClass") of the class used as value. If you can sort out a mistake by myself, I would like you to file a bug report. BBFN, Jonathan setClass("newClass", representation(value="numeric")) setMethod(f = "initialize",

Hi, I recognized that the function 'setReplaceMethod' is creating a character vector in the user workspace having the name (e.g. "newClass") of the class used as value. If you can sort out a mistake by myself, I would like you to file a bug report. BBFN, Jonathan setClass("newClass", representation(value="numeric")) setMethod(f = "initialize",

Hi If x <- 1:10 then x[5] <- 1i will promote x to be a complex vector. Suppose I have an S4 class "brob", and have functions is.brob(), as.brob(), as.numeric() and so forth (minimal self-contained code below). If x is numeric (1:10, say) and y is a brob, what is the best way to make x[5] <- y promote x to a brob in the same way as the complex example? Or is