MultiSearch

APP_ERROR MultiSearch(std::vector<AscendIndexVStar*>& indexes, const AscendIndexSearchParams& params, bool merge) const;

Queries the feature vectors for multiple AscendIndexVStar libraries and returns the distance and IDs of the most similar topK features based on the input feature vectors.

std::vector<AscendIndexVStar*>& indexes: multiple indexes to perform retrieval.

const AscendIndexSearchParams& params: search parameter. For details, see AscendIndexSearchParams.

size_t n: number of feature vectors to be queried.

std::vector<float>& queryData: feature vector data.

int topK: number of the most similar results to be returned.

bool merge: whether to merge the retrieval results of multiple indexes.

std::vector<float>& dists: distance between a vector and the topK nearest vectors.

std::vector<int64_t>& labels: IDs of the topK nearest vectors that are queried.

APP_ERROR: return status. For details, see Return Code Reference.

• n ∈ (0, 10000]. Ensure that the value of n × dim × sizeof(float) is less than the remaining memory of the card. Otherwise, the retrieval may fail due to insufficient memory.
• Length of queryData ≥ n × dim
• topK ∈ (0, 4096]
• dists and labels must meet the following requirements:
  • merge = true: The length must be greater than or equal to n × topK.
  • merge = false: The length must be greater than or equal to indexes.size() × n × topK.
• indexes must meet the requirement: 0 < indexes.size() ≤ 150.