How do I use the functions from the compiled rstan model?

So I have tried to do,

```
meta_model2r <- rstan::read_stan_csv(fit$output_files())
rstan_mod <- stan_model("model.stan")
loo_model <- loo(meta_model2r)
loo3 <- loo::loo_moment_match.default(
x = meta_model2r,
loo = loo_model,
post_draws = post_draws_stanfit,
log_lik_i = log_lik_i_stanfit,
unconstrain_pars = unconstrain_pars_stanfit,
log_prob_upars = log_prob_upars_stanfit,
log_lik_i_upars = log_lik_i_upars_stanfit,
cores = 2
)
```

With functions (from here) ,

```
# create a named list of draws for use with rstan methods
.rstan_relist <- function(x, skeleton) {
out <- utils::relist(x, skeleton)
for (i in seq_along(skeleton)) {
dim(out[[i]]) <- dim(skeleton[[i]])
}
out
}
# rstan helper function to get dims of parameters right
.create_skeleton <- function(pars, dims) {
out <- lapply(seq_along(pars), function(i) {
len_dims <- length(dims[[i]])
if (len_dims < 1) return(0)
return(array(0, dim = dims[[i]]))
})
names(out) <- pars
out
}
# extract original posterior draws
post_draws_stanfit <- function(x, ...) {
as.matrix(x)
}
# compute a matrix of log-likelihood values for the ith observation
# matrix contains information about the number of MCMC chains
log_lik_i_stanfit <- function(x, i, parameter_name = "log_lik", ...) {
loo::extract_log_lik(x, parameter_name, merge_chains = FALSE)[, , i]
}
# transform parameters to the unconstrained space
unconstrain_pars_stanfit <- function(x, pars, ...) {
skeleton <- .create_skeleton(x@sim$pars_oi, x@par_dims[x@sim$pars_oi])
upars <- apply(pars, 1, FUN = function(theta) {
rstan::unconstrain_pars(x, .rstan_relist(theta, skeleton))
})
# for one parameter models
if (is.null(dim(upars))) {
dim(upars) <- c(1, length(upars))
}
t(upars)
}
# compute log_prob for each posterior draws on the unconstrained space
log_prob_upars_stanfit <- function(x, upars, ...) {
apply(upars, 1, rstan::log_prob, object = x,
adjust_transform = TRUE, gradient = FALSE)
}
# compute log_lik values based on the unconstrained parameters
log_lik_i_upars_stanfit <- function(x, upars, i, parameter_name = "log_lik",
...) {
S <- nrow(upars)
out <- numeric(S)
for (s in seq_len(S)) {
out[s] <- rstan::constrain_pars(x, upars = upars[s, ])[[parameter_name]][i]
}
out
}
```