Set the categorical features of an lgb.Dataset object. Use this function
to tell LightGBM which features should be treated as categorical.
lgb.Dataset.set.categorical(dataset, categorical_feature)object of class lgb.Dataset
categorical features. This can either be a character vector of feature
names or an integer vector with the indices of the features (e.g.
c(1L, 10L) to say "the first and tenth columns").
the dataset you passed in
# \donttest{
setLGBMthreads(2L)
data.table::setDTthreads(1L)
data(agaricus.train, package = "lightgbm")
train <- agaricus.train
dtrain <- lgb.Dataset(train$data, label = train$label)
data_file <- tempfile(fileext = ".data")
lgb.Dataset.save(dtrain, data_file)
#> [LightGBM] [Info] Saving data to binary file /tmp/Rtmp22BmwX/file114b6e7e3d38.data
dtrain <- lgb.Dataset(data_file)
lgb.Dataset.set.categorical(dtrain, 1L:2L)
# }