haystack/docs/v1.2.0/_src/api/api/other.md

Module docs2answers

Docs2Answers

class Docs2Answers(BaseComponent)

This Node is used to convert retrieved documents into predicted answers format. It is useful for situations where you are calling a Retriever only pipeline via REST API. This ensures that your output is in a compatible format.

Module join_docs

JoinDocuments

class JoinDocuments(BaseComponent)

A node to join documents outputted by multiple retriever nodes.

The node allows multiple join modes:

• concatenate: combine the documents from multiple nodes. Any duplicate documents are discarded.
• merge: merge scores of documents from multiple nodes. Optionally, each input score can be given a different weight & a top_k limit can be set. This mode can also be used for "reranking" retrieved documents.
• reciprocal_rank_fusion: combines the documents based on their rank in multiple nodes.

__init__

def __init__(join_mode: str = "concatenate", weights: Optional[List[float]] = None, top_k_join: Optional[int] = None)

Arguments:

• join_mode: concatenate to combine documents from multiple retrievers merge to aggregate scores of individual documents, reciprocal_rank_fusion to apply rank based scoring.
• weights: A node-wise list(length of list must be equal to the number of input nodes) of weights for adjusting document scores when using the merge join_mode. By default, equal weight is given to each retriever score. This param is not compatible with the concatenate join_mode.
• top_k_join: Limit documents to top_k based on the resulting scores of the join.