Check whether a model's C++ forest is still alive

The C++ forest does not survive saveRDS(); an rpf object, or an rpf_pruned one fitted with keep_forest = TRUE, restored via readRDS() without rpf_marshal()/rpf_unmarshal() is unusable, and predict() on it is an error that says so. A pruned model without its forest (keep_forest = FALSE, the default) has no C++ forest and is always valid; the fit of such a model is not (it has no forest to use).

Usage

rpf_is_valid(x)

Arguments

x

[rpf | rpf_pruned]: A fitted rpf model, or a pruned one from prune_components(), possibly restored from disk.

Value

TRUE if the underlying model can be used, FALSE otherwise (also for the fit of a pruned model without its forest).

See also

rpf_marshal() to save a model so that it can be restored.

Examples

fit <- rpf(mpg ~ wt + cyl, data = mtcars, n_families = 10, prune = FALSE)
tmp <- tempfile(fileext = ".rds")

# saveRDS() alone loses the C++ forest
saveRDS(fit, tmp)
rpf_is_valid(readRDS(tmp))
#> [1] FALSE

# rpf_marshal() keeps it
saveRDS(rpf_marshal(fit), tmp)
rpf_is_valid(rpf_unmarshal(readRDS(tmp)))
#> [1] TRUE
unlink(tmp)