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Operating system information

Linux

Python version information

3.10

DB-GPT version

main

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Installation Information

• Installation From Source

• Docker Installation

• Docker Compose Installation

• Cluster Installation

• AutoDL Image

• Other

Device information

Device CPU

Models information

RerankModel: bge-rerank-base

What happened

When using CrossEncoderRanker as a ranker for EmbeddingRetrieve, calling the rank function of CrossEncoderRanker results in an "index out of bounds" error when the length of the retrieved results is 0.

What you expected to happen

1. self._rerank.rank(new_candidates_with_score, query) -> self._model.predict(sentences=query_content_pairs) -> if isinstance(sentences[0], str):
2. the value of new_candidates_with_score may be [] sometimes.

How to reproduce

ranker = CrossEncoderRanker(topk=3, model=os.path.join(MODEL_PATH, rerank_model))
ranker.rank(candidates_with_scores=[], query="what happened")

Additional context

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR!