Question

R Beginner here.

I have a list of class references. Each class has a field, “x”. I want to find the class reference which has the lowest “x” in the list.

In python I would do this:

return min(item.x for item in myList)

I’m not sure if there is specific terminology for the type of statement above (if someone knows I would like to know), but is there are way of doing a similar type of thing in R ?

If not, what would be the best way to achieve this in R ?

** Edit re. Justins comment

Here is how the list is created ..

mylist <- list()
for (i in 1:10){
    mylist <- c(mylist, MyClass$new())
}

where:

MyClass <- setRefClass("MyClass",
                        fields = list(x = "numeric"),
                        methods = list(
                           initialize = function(){
                               x <<- sample(0:100, 1)
                           }
                        )
)

Many thanks

Answer 1

If you want to get to the entire instance of MyClass with the lowest value of x, as opposed to just the minimum value of x (you seem to be looking for the former), consider using which.min in something like the following:

mylist[[which.min(lapply(mylist, function(myClass) myClass$x))]]