vectorize.py 文件源码

def custom_fnames(union):
    feature_names = []
    for name, trans, weight in union._iter():
        if hasattr(trans, 'get_feature_names'):
            this_fn = trans.get_feature_names()

        elif isinstance(trans, Pipeline):
            # we use pipelines to scale only specific attributes.
            # In this case, the vectorizer is first in the pipe.
            this_fn = trans.steps[0][-1].get_feature_names()

        else:
            raise AttributeError("Transformer %s (type %s) does not "
                                 "provide get_feature_names." % (
                                     str(name), type(trans).__name__))
        feature_names.extend([name + "__" + f for f in this_fn])
    return feature_names