retrieval
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Full text search engine in js. Features BM25 ranking function that can be tuned.
12 lines (11 loc) • 359 B
JavaScript
/*
* Function applying the BM25 formula to key parameters.
*/
module.exports = (function() {
return function(tf, idf, relDL, K=1.6, B=0.75)
{
let verbose = (B * relDL) + 1 - B;
let tfSaturate = tf / (K * verbose + tf);
return idf * tfSaturate; // computes the bm25 weight using its formula
};
})();