Functions to finalize data-specific parameter ranges
These functions take a parameter object and modify the unknown parts of
ranges based on a data set and simple heuristics.
finalize(object, ...) ## S3 method for class 'list' finalize(object, x, force = TRUE, ...) ## S3 method for class 'param' finalize(object, x, force = TRUE, ...) ## S3 method for class 'parameters' finalize(object, x, force = TRUE, ...) ## S3 method for class 'logical' finalize(object, x, force = TRUE, ...) ## Default S3 method: finalize(object, x, force = TRUE, ...) get_p(object, x, log_vals = FALSE, ...) get_log_p(object, x, ...) get_n_frac(object, x, log_vals = FALSE, frac = 1/3, ...) get_n_frac_range(object, x, log_vals = FALSE, frac = c(1/10, 5/10), ...) get_n(object, x, log_vals = FALSE, ...) get_rbf_range(object, x, seed = sample.int(10^5, 1), ...) get_batch_sizes(object, x, frac = c(1/10, 1/3), ...)
object |
A |
... |
Other arguments to pass to the underlying parameter
finalizer functions. For example, for |
x |
The predictor data. In some cases (see below) this should only include numeric data. |
force |
A single logical that indicates that even if the parameter object is complete, should it update the ranges anyway? |
log_vals |
A logical: should the ranges be set on the log10 scale? |
frac |
A double for the fraction of the data to be used for the upper
bound. For |
seed |
An integer to control the randomness of the calculations. |
finalize() runs the embedded finalizer function contained in the param
object (object$finalize) and returns the updated version. The finalization
function is one of the get_*() helpers.
The get_*() helper functions are designed to be used with the pipe
and update the parameter object in-place.
get_p() and get_log_p() set the upper value of the range to be
the number of columns in the data (on the natural and
log10 scale, respectively).
get_n() and get_n_frac() set the upper value to be the number of
rows in the data or a fraction of the total number of rows.
get_rbf_range() sets both bounds based on the heuristic defined in
kernlab::sigest(). It requires that all columns in x be numeric.
An updated param object or a list of updated param objects depending
on what is provided in object.
library(dplyr)
car_pred <- select(mtcars, -mpg)
# Needs an upper bound
mtry()
finalize(mtry(), car_pred)
# Nothing to do here since no unknowns
penalty()
finalize(penalty(), car_pred)
library(kernlab)
library(tibble)
library(purrr)
params <-
tribble(
~parameter, ~object,
"mtry", mtry(),
"num_terms", num_terms(),
"rbf_sigma", rbf_sigma()
)
params
# Note that `rbf_sigma()` has a default range that does not need to be
# finalized but will be changed if used in the function:
complete_params <-
params %>%
mutate(object = map(object, finalize, car_pred))
complete_params
params %>% dplyr::filter(parameter == "rbf_sigma") %>% pull(object)
complete_params %>% dplyr::filter(parameter == "rbf_sigma") %>% pull(object)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.