Exemplo n.º 1
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 internal BM25DocScorer(BM25Similarity outerInstance, BM25Stats stats, NumericDocValues norms)
 {
     this.outerInstance = outerInstance;
     this.stats         = stats;
     this.weightValue   = stats.Weight * (outerInstance.k1 + 1);
     this.cache         = stats.Cache;
     this.norms         = norms;
 }
Exemplo n.º 2
0
 internal BM25DocScorer(BM25Similarity outerInstance, BM25Stats stats, NumericDocValues norms)
 {
     this.OuterInstance = outerInstance;
     this.Stats         = stats;
     this.WeightValue   = stats.Weight * (outerInstance.K1_Renamed + 1);
     this.Cache         = stats.Cache;
     this.Norms         = norms;
 }
Exemplo n.º 3
0
        private Explanation ExplainScore(int doc, Explanation freq, BM25Stats stats, NumericDocValues norms)
        {
            Explanation result = new Explanation();

            result.Description = "score(doc=" + doc + ",freq=" + freq + "), product of:";

            Explanation boostExpl = new Explanation(stats.QueryBoost * stats.TopLevelBoost, "boost");

            if (boostExpl.Value != 1.0f)
            {
                result.AddDetail(boostExpl);
            }

            result.AddDetail(stats.Idf);

            Explanation tfNormExpl = new Explanation();

            tfNormExpl.Description = "tfNorm, computed from:";
            tfNormExpl.AddDetail(freq);
            tfNormExpl.AddDetail(new Explanation(k1, "parameter k1"));
            if (norms == null)
            {
                tfNormExpl.AddDetail(new Explanation(0, "parameter b (norms omitted for field)"));
                tfNormExpl.Value = (freq.Value * (k1 + 1)) / (freq.Value + k1);
            }
            else
            {
                float doclen = DecodeNormValue((byte)norms.Get(doc));
                tfNormExpl.AddDetail(new Explanation(b, "parameter b"));
                tfNormExpl.AddDetail(new Explanation(stats.Avgdl, "avgFieldLength"));
                tfNormExpl.AddDetail(new Explanation(doclen, "fieldLength"));
                tfNormExpl.Value = (freq.Value * (k1 + 1)) / (freq.Value + k1 * (1 - b + b * doclen / stats.Avgdl));
            }
            result.AddDetail(tfNormExpl);
            result.Value = boostExpl.Value * stats.Idf.Value * tfNormExpl.Value;
            return(result);
        }
Exemplo n.º 4
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        public override sealed SimScorer GetSimScorer(SimWeight stats, AtomicReaderContext context)
        {
            BM25Stats bm25stats = (BM25Stats)stats;

            return(new BM25DocScorer(this, bm25stats, context.AtomicReader.GetNormValues(bm25stats.Field)));
        }
Exemplo n.º 5
0
        private Explanation ExplainScore(int doc, Explanation freq, BM25Stats stats, NumericDocValues norms)
        {
            Explanation result = new Explanation();
            result.Description = "score(doc=" + doc + ",freq=" + freq + "), product of:";

            Explanation boostExpl = new Explanation(stats.QueryBoost * stats.TopLevelBoost, "boost");
            if (boostExpl.Value != 1.0f)
            {
                result.AddDetail(boostExpl);
            }

            result.AddDetail(stats.Idf);

            Explanation tfNormExpl = new Explanation();
            tfNormExpl.Description = "tfNorm, computed from:";
            tfNormExpl.AddDetail(freq);
            tfNormExpl.AddDetail(new Explanation(K1_Renamed, "parameter k1"));
            if (norms == null)
            {
                tfNormExpl.AddDetail(new Explanation(0, "parameter b (norms omitted for field)"));
                tfNormExpl.Value = (freq.Value * (K1_Renamed + 1)) / (freq.Value + K1_Renamed);
            }
            else
            {
                float doclen = DecodeNormValue((sbyte)norms.Get(doc));
                tfNormExpl.AddDetail(new Explanation(b, "parameter b"));
                tfNormExpl.AddDetail(new Explanation(stats.Avgdl, "avgFieldLength"));
                tfNormExpl.AddDetail(new Explanation(doclen, "fieldLength"));
                tfNormExpl.Value = (freq.Value * (K1_Renamed + 1)) / (freq.Value + K1_Renamed * (1 - b + b * doclen / stats.Avgdl));
            }
            result.AddDetail(tfNormExpl);
            result.Value = boostExpl.Value * stats.Idf.Value * tfNormExpl.Value;
            return result;
        }
Exemplo n.º 6
0
 internal BM25DocScorer(BM25Similarity outerInstance, BM25Stats stats, NumericDocValues norms)
 {
     this.OuterInstance = outerInstance;
     this.Stats = stats;
     this.WeightValue = stats.Weight * (outerInstance.K1_Renamed + 1);
     this.Cache = stats.Cache;
     this.Norms = norms;
 }