Displaying 20 results from an estimated 10000 matches similar to: "classes and methods"
2003 Nov 19
2
Was: setValidity and "initialize" method conflict ? [in R-help]
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
2007 Jul 25
2
initalizing and checking validity of S4 classes
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
2008 Apr 15
1
Pb with validObject(..., complete=TRUE)
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))
2007 Dec 23
1
Problem with initialize of S4 classes
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
2015 May 28
3
S4 inheritance and old class
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")
2008 Feb 29
1
Problems initializing an extended S4 class
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
2009 Jul 09
1
How to: initialize, setValidity, copy-constructor
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
2007 Apr 19
2
setClass inside a function
Hello,
I would like to create a function that gets passed a class name and then calls setClass, and a few other functions, inside. I have done this in the past with setmethod, creating accessors for all slots in a set of S4 classes. But setClass is choking when my function is called isnide a package, telling about an error in exists(cname, where). I assume this to be a problem with the
2003 Mar 17
1
What does is() mean?
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
2019 Aug 19
1
class() bug when used within a validity method
Hi,
This is a long-standing bug where 'class(object)' does not
return the actual class of 'object' when used inside a validity
method. Instead it seems to return the class for which the validity
method is defined. For example:
setClass("A", slots=c(stuff="ANY"))
setValidity("A", function(object) {
cat("validating an object of
2008 May 07
1
optional setValidity()
Hi
Suppose I have an S4 class "foo" and a validity checking
function ".checkfoo()":
setClass("foo", representation=representation("numeric"))
setValidity("foo" , .checkfoo)
is fine; in my application, .checkfoo() verifies that a bunch
of necessary conditions are met.
But .checkfoo() is very time consuming and I want
to give users the option
2003 Aug 24
2
setClass question
I would like to add a class to the SparseM package. I have a class "matrix.csr"
that describes a matrix in compressed sparse row format, now I would like a class
matrix.diag.csr that describes such objects when they happen to be diagonal.
The idea is that matrix.diag.csr objects should behave (later in life) exactly like
matrix.csr objects, the distinction is only needed in order to
2010 Mar 08
1
setClass or setValidity?
Hi,
I'm reading up on S4 classes *). There seem to be at least two ways of input validation:
setClass() (using the 'validity' argument) and setValidity(). Is it a matter of taste which function is used? Or should more complex validation code better be put in a setValiditity call?
*) A (Not So) Short Introduction to S4 Object Oriented Programming in R
V0.5.1 Christophe Genolini
2007 Mar 04
1
Problem using callNextMethod() in S4
Dear all,
Maybe, I am doing something wrong, but using R-2.5.0 on my Intel-Mac, I
have problems
using function callNextMethod() in method initialize.
I am loading the following code as file "testS4.R":
setClass("baseClass",
representation(myname = "character",
mydir = "character",
"VIRTUAL"),
2015 May 12
2
Unexpected failure when calling new() with unnamed arg and
Hi,
The man page for new() suggests that if 'a' is an object with slots
"slot1" and "slot2" and C is a class that extends the class of 'a',
then the 2 following calls should be equivalent:
new("C", a, ...)
new("C", slot1=a at slot1, slot2=a at slot2, ...)
This is generally the case but I just ran into a situation where it's
not.
2009 Aug 17
2
S4: inheritance of validity methods?
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"),
2009 Oct 26
1
Why 'validity' is not called? (S4)
I thought that 'validity' defined in 'setClass' should be called in
'new'. Could somebody let me know why 'validity' is not called? How to
make it be called?
> setClass(
+ Class='A',
+ representation=representation(
+ x='numeric'
+ ),
+ validity=function(object){
+ cat("~~~ A: inspector ~~~\n")
+
2012 Jan 10
1
Can "prototype" and "initialize" coexist?
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",
+
2015 May 13
2
Unexpected failure when calling new() with unnamed arg and
Thanks Martin for looking into this. H.
On 05/13/2015 03:57 AM, Martin Maechler wrote:
>>>>>> Herv? Pag?s <hpages at fredhutch.org>
>>>>>> on Tue, 12 May 2015 15:18:42 -0700 writes:
>
>> Hi,
>
>> The man page for new() suggests that if 'a' is an object with slots
>> "slot1" and "slot2" and C is a
2007 Mar 31
1
Problem with S4 inheritance: unexpected re-initialization?
Dear all,
To explain my problem I am attaching a demonstration package "myclasspkg":
I have the following two S4 classes with similar inheritance:
SubSubClassA <- SubClassB <- BaseClass
SubSubClassB <- SubClassB <- BaseClass
In R I am calling the following functions:
> library(myclasspkg)
> subA <-