[R] The equivalent of which() when accessing slots in an object

[Bob Rudis]

    which(purrr::map_dbl(buylist, slot, "reqstock") > 100)

or

    which(sapply(buylist, slot, "reqstock") > 100)

ought to do the trick.

On Mon, Oct 31, 2016 at 10:09 AM, Thomas Chesney
<Thomas.Chesney at nottingham.ac.uk> wrote:
> I have the following object
>
> setClass("buyer",
> representation(
> reqstock="numeric",
> buyout="numeric"),
> )
>
> nBuy <- 5
>
> #Set buyer parameters here
> buylist <- list()
> for (i in 1:nBuy){
> buylist[[i]] <- new("buyer")
> buylist[[i]]@reqstock <- sample(c(50:200),1)
> }
>
> and want to count the number of objects in buylist that have reqstock greater than 100. Something like this if it was a vector:
>
> length(which(buylist[[]]@reqstock > 100))
>
> How could I do this please and where could I find more information about manipulating slots? When I try to search for this I just keep finding info on ls() and similar functions.
>
> Thank you
>
> Thomas Chesney
> http://www.nottingham.ac.uk/~liztc/Personal/index.html
>
>
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