R recipes step_spatialsign 空間符號預處理

step_spatialsign(
  recipe,
  ...,
  role = "predictor",
  na_rm = TRUE,
  trained = FALSE,
  columns = NULL,
  skip = FALSE,
  id = rand_id("spatialsign")
)

其他多元變換步驟：step_classdist_shrunken() , step_classdist() , step_depth() , step_geodist() , step_ica() , step_isomap() , step_kpca_poly() , step_kpca_rbf() , step_kpca() , step_mutate_at() , step_nnmf_sparse() , step_nnmf() , step_pca() , step_pls() , step_ratio()

data(biomass, package = "modeldata")

biomass_tr <- biomass[biomass$dataset == "Training", ]
biomass_te <- biomass[biomass$dataset == "Testing", ]

rec <- recipe(
  HHV ~ carbon + hydrogen + oxygen + nitrogen + sulfur,
  data = biomass_tr
)

ss_trans <- rec %>%
  step_center(carbon, hydrogen) %>%
  step_scale(carbon, hydrogen) %>%
  step_spatialsign(carbon, hydrogen)

ss_obj <- prep(ss_trans, training = biomass_tr)

transformed_te <- bake(ss_obj, biomass_te)

plot(biomass_te$carbon, biomass_te$hydrogen)


plot(transformed_te$carbon, transformed_te$hydrogen)


tidy(ss_trans, number = 3)
#> # A tibble: 2 × 2
#>   terms    id               
#>   <chr>    <chr>            
#> 1 carbon   spatialsign_Geidk
#> 2 hydrogen spatialsign_Geidk
tidy(ss_obj, number = 3)
#> # A tibble: 2 × 2
#>   terms    id               
#>   <chr>    <chr>            
#> 1 carbon   spatialsign_Geidk
#> 2 hydrogen spatialsign_Geidk