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Create Feature Selection Design Matrix

Source: R/wvim-design-matrix.R
wvim_design_matrix.Rd

Creates a logical design matrix for leave-in or leave-out feature evaluation. Used internally with mlr3fselect to evaluate feature subsets.

Usage

wvim_design_matrix(
  all_features,
  feature_names = all_features,
  direction = c("leave-out", "leave-in")
)

Arguments

all_features

(character()) All available feature names from the task.

feature_names

(character() | list of character()) Features or feature groups to evaluate. Can be a vector for individual features or a named list for grouped features. Defaults to all_features if unspecified.

direction

(character(1)) Either "leave-in" or "leave-out" (default). Controls which features are selected in the design matrix. "leave-out" sets features of interest to FALSE, and "leave-in" analogously sets them to TRUE.

Value

data.table with logical columns for each feature in all_features and length(feature_names) rows, one for each entry in feature_names

Examples

task = mlr3::tsk("mtcars")

# Individual features
feature_names = task$feature_names[1:3]
wvim_design_matrix(task$feature_names, feature_names, "leave-in")
#>        am   carb    cyl   disp   drat   gear     hp   qsec     vs     wt
#>    <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl>
#> 1:   TRUE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE
#> 2:  FALSE   TRUE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE
#> 3:  FALSE  FALSE   TRUE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE  FALSE
wvim_design_matrix(task$feature_names, feature_names, "leave-out")
#>        am   carb    cyl   disp   drat   gear     hp   qsec     vs     wt
#>    <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl>
#> 1:  FALSE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE
#> 2:   TRUE  FALSE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE
#> 3:   TRUE   TRUE  FALSE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE

# Feature groups
feature_groups = list(
  A = task$feature_names[1:2],
  B = task$feature_names[3:5]
)
wvim_design_matrix(task$feature_names, feature_groups, "leave-out")
#>        am   carb    cyl   disp   drat   gear     hp   qsec     vs     wt
#>    <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl> <lgcl>
#> 1:  FALSE  FALSE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE   TRUE
#> 2:   TRUE   TRUE  FALSE  FALSE  FALSE   TRUE   TRUE   TRUE   TRUE   TRUE