get_design {sfd}

Retrieve a Space-Filling Design

Description

Obtain a space-filling design (if possible) based on how many characteristics (i.e. parameters) and size (i.e., number of grid points).

Usage

get_design(num_param, num_points, type = "any")

Arguments

num_param

An integer between two and ten for the number of characteristics/factors/parameters in the design.

num_points

An integer for the number of grid points requested. If there is no corresponding design, an error is given (when using get_design())

type

A character string with possible values> "any", "audze_eglais", "max_min_l1", "max_min_l2", and "uniform". A value of "any" will choose the first design available (in alphabetical order).

Details

The "audze_eglais", "max_min_l1", and "max_min_l2" designs are from https://www.spacefillingdesigns.nl/.

The uniform designs were pre-computed using mixtox::unidTab() using the method of Wang and Fang (2005) using the C2 criterion.

Value

A tibble (data frame) with columns named X1 to ⁠X{num_param}⁠. Each column is an integer for the ordered value of the real parameter values.

References

https://www.spacefillingdesigns.nl/, Husslage, B. G., Rennen, G., Van Dam, E. R., & Den Hertog, D. (2011). Space-filling Latin hypercube designs for computer experiments. Optimization and Engineering, 12, 611-630. Wang, Y., & Fang, K. (2005). Uniform design of experiments with mixtures. In Selected Papers Of Wang Yuan, 468-479.

Examples

if (rlang::is_installed("ggplot2")) {
 library(ggplot2)

 two_param_l2 <- get_design(2, 100, type = "audze_eglais")

 ggplot(two_param_l2, aes(X1, X2)) +
   geom_point() +
   coord_equal()
}

no_design <- try(get_design(2, 1000), silent = TRUE)
cat(as.character(no_design))