.. _preprocessing-sklearn-integration: Scikit-learn integration ======================== Both encoders follow estimator conventions closely enough to participate in pipeline-style workflows. Keep the encoder inside the fitted preprocessing pipeline so category state is learned only from training data. Use ``get_feature_names_out`` when downstream diagnostics or model explainers need a stable mapping from encoded columns back to source features. Sparse output can reduce memory use for high-cardinality categories, but downstream estimators must accept sparse input. Do not call ``fit_transform`` independently on train and test sets.