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rclassr-s4

Define an S4 class with slots that have their class definitions in another package

I would like to define an S4 class in R. One of the slots should contain an mcmc object as defined in the coda package. I tried the following:

library("coda")
setClass(Class = "myClass", representation = representation(var = "mcmc"))

But this results in a warning:

Undefined slot classes in the definition of "myClass": var(class "mcmc")

The class definition does not work later on and throws an error message because var has an "undefined class".

How can I tell the setClass command where to look for the definition of mcmc objects?

Solution

  • I believe this is because mcmc is an S3 class and not a formal S4 class. You would need to use setOldClass to register the S3 as a formally defined class.

    setOldClass("mcmc")
setClass(Class = "myClass", representation = representation(var = "mcmc"))