similar to: Default arguments for setMethod() (PR#8021)

Displaying 20 results from an estimated 10000 matches similar to: "Default arguments for setMethod() (PR#8021)"

2006 Oct 19
1
default arguments in generics and methods
i believe the following is true but would appreciate confirmation that it is intended behavior and will continue: if a default argument is employed in the definition of a generic function, and the generic is called with the argument in question (call it 'ARG') missing, then the method for signature (..., ARG = "missing", ...) will be called by 'standardGeneric'
2006 Mar 22
1
setting argument defaults in setMethod
Hi, I want to set a default value in a method of a generic function. This seems as though it should be possible. From R help on setMethod... Method definitions can have default expressions for arguments. If those arguments are then missing in the call to the generic function, the default expression in the method is used. If the method definition has no default for the
2006 Feb 14
3
S4 classes and methods with optional arguments
Hi, i have used S4 classes to implement a unified access to random number generators (package rstream on CRAN). I have used a construct to allow optional arguments: if(!isGeneric("rstream.sample")) setGeneric("rstream.sample", function(stream,...) standardGeneric("rstream.sample")) setMethod("rstream.sample",
2013 Feb 14
4
2 setGeneric's, same name, different method signatures
hi. below is a small test case (hopefully minimal, though i'm still a bit confused about initializers). i would have guessed (and maybe i still would have been right) that one could re-use the name of a generic function for functions with different numbers of arguments. in the case below, class A's bB() queries the status of a single A object, so bB(A) (where here "A" is an
2010 Sep 03
3
S4 Method Signatures
Hello, If the signature of a method defines which generic it implements then I'm confused about why this minimal example I invented won't work : setGeneric("myFun", function(rs, ...){standardGeneric("myFun")}) setGeneric("myFun", function(cs, ...){standardGeneric("myFun")}) setMethod("myFun", "numeric", function(rs, colour =
2009 Oct 27
1
How to reduce key strokes when defining S4 classes?
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' )
2009 Jun 05
2
Problem with generic methods
Hi I want to create a new generic method, but I end up with an error (evaluation nested too deeply). see the transcript below. The function beginYear.Fun() works, but not beginYear. I have no idea why. Any ideas welcome, Rainer > setClass("fun", representation(x = "numeric")) [1] "fun" > new("fun") An object of class ?fun? Slot "x":
2008 May 10
2
Hashes as S4 Classes, or: How to separate environments
For learning purposes mainly I attempted to implement hashes/maps/dictionaries (Python lingua) as S4 classes, see the coding below. I came across some rough S4 edges, but in the end it worked (for one dictionary). When testing ones sees that the dictionaries D1 and D2 share their environments D1 at hash and D2 at hash, though I thought a new and empty environment would be generated each time
2012 Aug 05
2
setMethod sometimes fails to set package slot when signature has trailing 'ANY'
after this setClass("A") setGeneric("bar", function(x, y) standardGeneric("bar")) setMethod(bar, signature(x="A", y="A"), function(x, y) {}) setMethod(bar, signature(x="A", y="ANY"), function(x, y) {}) the method for signature c("A", "A") contains package information > str(getMethod(bar,
2012 Nov 21
1
S3 generic/method consistency issue with R CMD check
Hi, I'm having some trouble setting methods for the qr family of functions. I believe I have distilled my misunderstanding in the code snippet below: foo <- function(x, ...) UseMethod("foo") foo.default <- function(x) { } # foo setGeneric(name = "foo", useAsDefault = foo) setMethod("foo", signature(x="bar"), function(x, ...) { } )
2006 Oct 11
1
dispatching on group generics with more than one formal
please see the code below. foo2 fails to dispatch correctly, but foo does fine. i have tried 'cacheMetaData(1)' and a number of different variants of 'cacheGenericsMetaData', on the possibility there is a caching issue. but i still can't sort it out. also one general question: does it really matter what's in the body of the function definition in a
2005 Mar 25
1
S4 methods semantics questions
Some quick questions about S4 methods. Does the typing of S4 methods mean that lazy evaluation is no longer possible? It seems that you would need to evaluate the arguments to determine their type at dispatch. Second, what role, if any, do default arguments play in S4 methods? I notice that you can put default arguments into generics but that the dispatch is still done on the type of the
2010 Mar 15
2
Strange behavior of assign in a S4 method.
Hi the list, I define a method that want to change an object without assignation (foo(x) and not x<-foo(x)) using deparse and assign. But when the argument of the method does not match *exactly* with the definition of the generic function, assign does not work... Anything wrong? Christophe #------ Does not work ------#
2008 Jan 22
1
deparse, substitute and S4 generics
Hello everyone, I encountered the following confusing behavior of 'deparse' and 'substitute' while programming with S4 classes (see example below). It seems like the presence of '...' argument in the definition of the generic generates the problem. I have no clue why, can anyone explain that to me? Are there any "workarounds"? Thanks a lot for your time!
2003 Sep 27
2
does isGeneric work differently in 1.8.0 ?
Hello, the last command (isGeneric) in following R-code (attached) produces different output, depending on wheter 1.8.0 alpha or 1.7.1 is used. Is that to be expected ? Both R Versions were started with option vanilla --------------------------------------------------- R.1.7.1: --------------------------------------------------- > version _ platform i686-pc-linux-gnu arch i686
2011 Aug 23
1
Implementing a "plugin" paradigm with R methods
Dear list, I was wondering how to best implement some sort of a "plugin" paradigm using R methods and the dispatcher: Say we have a function/method ('foo') that does something useful, but that should be open for extension in ONE specific area by OTHERS using my package. Of course they could go ahead and write a whole new 'foo' method including the features they'd
2010 Feb 08
1
using setMethod or setGeneric to change S4 accessor symbol from @ to $
I created some S4 objects that are essentially data frame objects. The S4 object definitions were necessary to verify data integrity and force a standardized data format. I am, however, finding myself redefining all the typical generic functions so that I can still manipulate my S4 objects as if they were data frames ... I have used setMethod to set methods for "subset",
2003 Dec 02
1
setMethod("min", "myclass", ...)
Hello, I have defined a new class > setClass("myclass", representation(min = "numeric", max = "numeric")) and want to write accessor functions, so that for > foo = new("myclass", min = 0, max = 1) > min(foo) # prints 0 > max(foo) # prints 1 At first i created a generic function for "min" > setGeneric("min",
2004 Jun 26
1
S4 group "Math", "getGroupMembers", "genericForPrimitive"
Hi, I found the following on Windows 2000/NT R Version 1.9.1 (2004-06-21) (also Version 1.9.0): The S4 group "Math" doesn't work as documented; i.e., "log", "log10", "gamma" and "lgamma" are included in the documentation but don't work. See example code below. Moreover, what about 'genericForPrimitive' which is used in
2006 Jan 25
2
Using substitute from inside an S4 method
Hi all, I would like to access the name of a variable passed to an S4 method. For a function, I would do this: f <- function(x) as.character(substitute(x)) This also works for a the examples I have tried for methods that do not have extra, non-dispatch args: setGeneric("A", function(x, ...) standardGeneric("A")) setMethod("A",