retrieval (npm): Full text search engine in js. Features BM25 ranking function that can be tuned.
Keywords: okapi bm25|tfidf|tf-idf|search engine|full text search|natural language search|information retrieval|bm25|term weighting|vector space model|full-text-search|information-retrieval|natural-language-processing|okapi-bm25|search-engine|term-weighting|tf-idf-vectorizer|tfidf-text-analysis|vector-space-model