similar to: Why 'validity' is not called? (S4)

Dear useRs and wizaRds, I am currently developing a set of functions using S4 classes. On the way I encountered the problem exemplified with the code below. For some reason the 'validity' method does not seem to work, i.e. does not check for errors in the specification of the slots of the defined class. Any hints? My understanding of the whole S4 system was that validity checks are made

Dear UseRs, Does anyone know when exactly the validity is checked in S4? Documentation is silent:(. Here is a small example: setClass("test1",representation(a="numeric")) setMethod("initialize","test1", function(.Object,...){ a<-runif(1) ## here slot "a" is initialized ## callNextMethod(.Object,a=a,...)

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' )

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 am having trouble extending S4 classes in cases where I'm using both validity and initialize methods. I've read as much S4 information as I can find, but I've yet to have that "a-ha" moment. In my application, I am using validity methods to guard against inappropriate input data that my code has no way of handling, and initialize methods to detect and deal

In the following code, 'multiply' doesn't multiply a at x by 2. I'm wondering how to define a method that can change the slot of a class. $ Rscript setGeneric.R > setClass( + Class='A', + representation=representation( + x='numeric' + ) + ) [1] "A" > > setMethod( + f='initialize', +

Hi, I recently ran into this problem. I couldn't find any mention of it in the setClass documentation. setClass("Foo", representation(file = "character")) setMethod("initialize", "Foo", function(.Object, file) { print(file) }) setClass("Bar", contains = "Foo") And the error: Error in print(file) : argument "file" is

Hello, Thomas Stabla (statho3@web.de) has already sent this question to R-help, Wed, 12 Nov 2003 21:21:31 +0100, but we are not sure whether we should better post this mail to this audience than to R-help: --------------------------------------------------------------------- We are using S4-classes and want to force a validity check when an object is created. How can this be done, when an

Suppose you have a class, say sex, for lack of a better example, and you are tempted, in defining the behavior of the call, is(x,"sex") to check whether certain basic features are satisfied, not to just trust the claim that x is specified to be of class "sex". `Without delving into details further sanity checking of the structure of the object is sometimes prudent to avoid

Hello list, I'm having troubles setting up a basic calss hierarchy with S4. Here is a simplified schema of what I'd like to do: - Two classes: A and B that extends A - Ensure that the slots added by B are consistent with the slots of A - Let A initialize itself (I'm not supposed to know the internal cooking of A) - By default set the slots of B based on the slots that A initialized

The documentation for validObject suggests that slots are checked for validity, but validObject seems only to check that the slot has something claiming to be correct; validObject(obj) does not perform the equivalent of validObject(obj at y) for slot y. This is also the second problem issue reported in http://tolstoy.newcastle.edu.au/R/devel/05/03/0151.html Relevant documentation, an example,

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")

Sirs: My validity function did not run when my class contains="matrix". But if I first define the class with contains="numeric", then define it again with contains="matrix", validity runs. Here's the session: > f <- function(object) "BAD CLASS" # force error to > setClass("A", contains="matrix", validity=f) [1]

Folks, My object oriented background is in Java and C++. I am a novice to using S4/object-oriented coding in R but not to R. Below is an example that I found that I have expanded on. I am not getting how "prototype" and "initialize" work together, if at all. Here is output from a short "session" > setClass("xx", +

Dear all Below is the code for "scriptPreFilter.R" which gives the following result: > source("scriptPreFilter.R") > prefltr <- new("PreFilter", mad=c(0.5,0.01)) [1] "------initialize:PreFilter------" [1] "------initialize:Filter------" > str(prefltr) Formal class 'PreFilter' [package ".GlobalEnv"] with 2 slots

Hi, When called with complete=TRUE, validObject() is supposed to work in a recursive manner. But here is a situation where it doesn't seem to be the case. Let's define a class with a validity method: setClass("PosInts", representation(ii="integer")) setValidity("PosInts", function(object) { if (!all(object at ii > 0))

Hi, I'm wondering if the following behaviour is normal: setClass('A', representation(number='numeric'), validity=function(object){ if( object at number < -1 ) return("Invalid number"); TRUE}) >[1] "A" a <- new('A') a >An object of class ?A? >Slot "number": >numeric(0) a at number <- 0 a at number <- -3 a >An

Hi all, I am having a problem trying to declare a slot representation to hold a file connection. With V2.8.0 I had been using: setClass("Element", representation( [other slots removed], datafileConn = setOldClass(c("file","connection")) ) ) This resulted in a warning but still ran okay. No however with V2.9.0 I am getting

Hi the list. I try to learn the S4 programming. I find the wiki and several doc. But I still have few questions... 1. To define 'representation', we can use two syntax : - representation=list(temps = 'numeric',traj = 'matrix') - representation(temps = 'numeric',traj = 'matrix') Is there any difference ? 2. 'validityMethod' check the

Hi, Given a simple three class hierarchy: A <-- B <-- C I want to define an initialize method for each class such that when I call new("C", x=5), the initialize methods for A and B are used to incrementally build the object. When I do what seems obvious to me using callNextMethod, I get an infinite recursion. An example follows... setClass("A",