# HybridLimitFactorPrescription

> **Class** in `langchain_astradb`

📖 [View in docs](https://reference.langchain.com/python/langchain-astradb/vectorstores/HybridLimitFactorPrescription)

A per-subsearch setting for the hybrid-search 'limit' factors.

This structure is to be used to set different values for
the vector and the lexical portions of the hybrid search.

Each of the attributes is a floating-point number, representing the multiplicative
factor applied to a search final 'k' to calculate the "limit" value for
the associated sub-search. For instance, if vector=1.5 and lexical=3.0,
a hybrid search called by asking a final set of k=4 results will be executed
with limits of 6 for vector and 12 for lexical. (The results are approximated
to an integer.)

## Signature

```python
HybridLimitFactorPrescription()
```

## Extends

- `NamedTuple`

## Properties

- `vector`
- `lexical`

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[View source on GitHub](https://github.com/langchain-ai/langchain-datastax/blob/f4a6aef74d38ee804b0d407e19359c6e45989068/libs/astradb/langchain_astradb/vectorstores.py#L128)