similar to: S4 class slot name 'names' is not allowed (PR#8767)

Martin, Thanks! I'll use name for now. Steve -----Original Message----- From: Martin Maechler [mailto:maechler at stat.math.ethz.ch] Sent: Thursday, April 13, 2006 3:11 AM To: Steven Lacey Cc: R-bugs at stat.math.ethz.ch; r-help at stat.math.ethz.ch Subject: S4 class slot name 'names' is not allowed >>>>> "SteveL" == Steven Lacey <slacey at

Hi, Why doesn't this work? setClass("test",representation(names="character")) tmp <- new("test") tmp@names <- "a" Error in "slot<-"(object, name, TRUE, value) : 'names' attribute [1] must be the same length as the vector [0] Why does this work (replace names with name)?

Hello, Besides the problem with using "names," one has a similar problem using ".Data" together with "VIRTUAL." Consider the top of p. 295 of the green book. This should work (I had to change "structure" to "junk" because "structure" is a sealed class definition): setClass("junk",

There are usually two directories involved in an install: the source directory and the install directory in R_HOME/library. The INSTALL procedure builds the package (usually in place in Windows, I'm not sure if that's the case in Unix) and installs it into the install directory by copying those files necessary to use it. REMOVE removes the install directory, cleaning up

Hi, This works fine. >setClass("a",representation(b="list",c="list")) >new("a",b=list(7)) >An object of class "a" Slot "b": [[1]] [1] 7 Slot "c": list() But, now suppose you want a slot to accept an object of class formula... >setClass("a",representation(b="list",c="formula"))

When I define an S4 class ("B" in the example below) that directly extends another ("A" in the example below) , which in turn directly extends another ("character" in the example below), I find that the slot does not have the class I specified in setClass(), it has the underlying class. Is this an intended feature? Briefly, the reason for using this type of

All, I am considering creating an S4 class whose slots (2) are both S4 classes. ?Since an S4 slot can be an S3 class I figure this can be done. ?However, the correct syntax of which I am unsure. ?Reviewing the docs I have come to the following conclusion: SetClass('myfoo', ? ? ? ? ? ? ? ? ? slots = (foo1, foo2)) Without a type I believe each slot is .Data. ?A get method on the above

Hi all, This feature was throwing me for a loop for quite some time until I played with the names of the slots. Consider exhibit A: ============== setClass("SVM", representation=representation( x='numeric', y='numeric', C='numeric', eps='numeric'), prototype=prototype( x=numeric(),

Dear all, Since my package is based on S4 classes, I would like to know how to add a slot to an existing S4 class without breaking the code of users of my package. Assume the following S4 class: setClass("MyClass", representation(name = "character", type = "character", data = "data.frame" ), prototype(name =

Thanks for the report. The issue is that one cannot set special attributes like names, dim, dimnames, etc on S4 objects. I was aready working on this and will have a fix soon. > a2 <- new("A2") > dim(a2) <- c(2, 3) Error in dim(a2) <- c(2, 3) : invalid first argument On Mon, Jun 5, 2017 at 6:08 PM, Herv? Pag?s <hpages at fredhutch.org> wrote: > Hi, > >

I have an S4 class with a slot of class "array", and in upgrading to 2.0.1 (from 1.9.1) I have encountered a change in behaviour. This causes me some difficulties if I want to allow 2-dimensional arrays in the slot. The following (in 2.0.1) illustrates the point: > setClass("foo",representation("array")) [1] "foo" > a <-

I have an S4 class with a slot of class "array", and in upgrading to 2.0.1 (from 1.9.1) I have encountered a change in behaviour. This causes me some difficulties if I want to allow 2-dimensional arrays in the slot. The following (in 2.0.1) illustrates the point: > setClass("foo",representation("array")) [1] "foo" > a <-

I've fixed this and will commit soon. Disregard my dim<-() example; that behaves as expected (the class needs a dim<-() method). Michael On Tue, Jun 6, 2017 at 5:16 AM, Michael Lawrence <michafla at gene.com> wrote: > Thanks for the report. The issue is that one cannot set special attributes > like names, dim, dimnames, etc on S4 objects. I was aready working on this >

Hi, It's nice to be able to define S4 classes with slots that correspond to standard attributes: setClass("A1", slots=c(names="character")) setClass("A2", slots=c(dim="integer")) setClass("A3", slots=c(dimnames="list")) By doing this, one gets a few methods for free: a1 <- new("A1", names=letters[1:3])

Dear listmembers, I would like to define a class with a slot that takes either an object of class aov or NULL. I have been reading "S4 Classes in 15 pages more or less" and "Lecture: S4 classes and methods" #First I tried with list and NULL setClass(listOrNULL") setIs("list", "listOrNULL") setIs("NULL", "listOrNULL") #doesn't

Thanks, Martin, that (inherit from a virtual class) worked great. I already had a base class created with setUnion, and so this was an easy switch. I had assumed that since inheriting from a class without slots would produce a class without slots the result would still be virtual. Fortunately that's not the case. Ross ________________________________________ From: Martin Morgan

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 How do I specify an S4 class with a slot that is potentially numeric, but NA by default? I want the slot to be NA until I calculate its value (an expensive operation, not needed for all applications). When its value is known, I will create a new object with the correct value inserted in the slot. I want "NA" to signify "not known". My attempt fails because

Dear R-developers I came across the following issue, which I find strange: setClass("A", representation(a = "numeric")) B <- list() myA <- new("A", a = 1) B$otherA <- myA B$otherA at a <- 2 myA at a Assigning a new value to slot 'a' in the _copy_ of myA stored in B$otherA changes the original value of myA -- this was surprising to me, and I

can list names attributes be preserved through S4 class containment? seems to be so but only if the containment relationship is direct ... see below. > setClass("c1", contains="list") [1] "c1" > l1 = list(a=1, b=2) > o1 = new("c1", l1) > names(o1) # pleasant surprise [1] "a" "b" > setClass("c2",