Retrieve list of training features names from classifier

Question

Is there a way to retrieve the list of feature names used for training of a classifier, once it has been trained with the fit method? I would like to get this i

Answer 1

I have a solution which works but is not very elegant. This is an old post with no existing solutions so I suppose there are not any.

Create and fit your model. For example

model = GradientBoostingRegressor(**params)
model.fit(X_train, y_train)

Then you can add an attribute which is the 'feature_names' since you know them at training time

model.feature_names = list(X_train.columns.values)

I typically then put the model into a binary file to pass it around but you can ignore this

joblib.dump(model, filename)
loaded_model = joblib.load(filename)

Then you can get the feature names back from the model to use them when you predict

f_names = loaded_model.feature_names
loaded_model.predict(X_pred[f_names])