Best practices for using stan model within a function

Interfaces RStan
,
1

I am developing an R package that uses stan. This involves calling functions that run stan within them.

As an example I have a function that generates fake data from a model using the stan “sampling” function, i.e.:

generateFakeData <- function(N,alpha,beta) {
   compiledStanModel <- stan_model("myStanModel.stan") 
   simulatedData <- sampling(
     compiledStanModel,
     data = list(N = N,
                 alpha = alpha,
 ...etc
}

This runs into problems as when I am calling the function with tests, etc. the stan model gets recompiled and at best I get a “recompiling to avoid crashing R session” message. At worst RStudio crashes.

I can just pass the compiledStanModel as a function parameter, but what is the best practice? Especially if this will eventually become a package. Should the model be a global variable somewhere?

Thank you in advance.

2

Are you using rstantools? The guide is very useful, and the package is intended to help you avoid the exact issue you are encountering :).

4 Likes
3

Thank you very much @hhau, I actually did use rstantools to setup the package but did not read carefully enough on the other aspects of the package. Thank you.