lenskit.pipeline.RecPipelineBuilder
===================================

.. py:class:: lenskit.pipeline.RecPipelineBuilder
   :canonical: lenskit.pipeline._common.RecPipelineBuilder

   Builder to help assemble common pipeline patterns.

   This is a convenience class; you can always directly assemble a
   :class:`Pipeline` if this class's behavior is inadquate.

   :Stability: Caller


   .. py:attribute:: is_predictor
      :type:  bool
      :value: False



   .. py:method:: scorer(score, config = None)

      Specify the scoring model.



   .. py:method:: ranker(rank = None, config = None, *, n = None)

      Specify the ranker to use.  If ``None``, sets up a :class:`TopNRanker`
      with ``n=n``.



   .. py:method:: candidate_selector(sel, config = None)

      Specify the candidate selector component.  The component should accept
      a query as its input and return an item list.



   .. py:method:: predicts_ratings(*, transform = None, fallback = None)

      Specify that this pipeline will predict ratings, optionally providing a
      rating transformer and fallback scorer for the rating predictions.

      :param transform: A component to transform scores prior to returning them.  If
                        supplied, it will be applied to both primary scores and fallback
                        scores.
      :param fallback: A fallback scorer to use when the primary scorer cannot score an
                       item. The fallback should accept ``query`` and ``items`` inputs,
                       and return an item list.



   .. py:method:: build(name = None)

      Build the specified pipeline.



   .. py:method:: reranker(reranker, config = None)

      Specify a reranker to add to the pipeline.

      :param reranker: The reranker to use in the pipeline.
      :param config: Configuration parameters to initialize the reranker if a reranker is specified.