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)the dataset you passed in
# \donttest{
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/RtmpViPAUB/file13c56441b443.data
dtrain <- lgb.Dataset(data_file)
lgb.Dataset.set.categorical(dtrain, 1L:2L)
# }