Java Code Examples for org.apache.lucene.search.CollectionStatistics#field()

The following examples show how to use org.apache.lucene.search.CollectionStatistics#field() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source File: SMARTBNNBNNSimilarity.java    From lucene4ir with Apache License 2.0 6 votes vote down vote up 
@Override
   public final SimWeight computeWeight(CollectionStatistics collectionStats,
				 TermStatistics... termStats)
   {
float N, n, idf, adl;
idf = 1.0f;
N   = collectionStats.maxDoc();
adl = collectionStats.sumTotalTermFreq() / N;

if (termStats.length == 1) {
    n = termStats[0].docFreq();
    idf = log(N/n);
}
else {
    for (final TermStatistics stat : termStats) {
	n = stat.docFreq();
	idf += log(N/n);
    }
}

return new TFIDFWeight(collectionStats.field(), idf, adl);
   }
Example 2
Source File: CollectionStats.java    From lucene-solr with Apache License 2.0 5 votes vote down vote up 
public CollectionStats(CollectionStatistics stats) {
  this.field = stats.field();
  this.maxDoc = stats.maxDoc();
  this.docCount = stats.docCount();
  this.sumTotalTermFreq = stats.sumTotalTermFreq();
  this.sumDocFreq = stats.sumDocFreq();
}
Example 3
Source File: BM25Similarity.java    From lucene4ir with Apache License 2.0 5 votes vote down vote up 
@Override
public final SimWeight computeWeight(CollectionStatistics collectionStats, TermStatistics... termStats) {
  Explanation idf = termStats.length == 1 ? idfExplain(collectionStats, termStats[0]) : idfExplain(collectionStats, termStats);

  float avgdl = avgFieldLength(collectionStats);

  // compute freq-independent part of bm25 equation across all norm values
  float cache[] = new float[256];
  for (int i = 0; i < cache.length; i++) {
    cache[i] = k1 * ((1 - b) + b * decodeNormValue((byte)i) / avgdl);
  }
  return new BM25Stats(collectionStats.field(), idf, avgdl, cache);
}
Example 4
Source File: OKAPIBM25Similarity.java    From lucene4ir with Apache License 2.0 5 votes vote down vote up 
@Override
   public final SimWeight computeWeight(CollectionStatistics collectionStats,
				 TermStatistics... termStats)
   {
long  N, n;
float idf_, avdl;

idf_ = 1.0f;

N    = collectionStats.docCount();
if (N == -1)
    N = collectionStats.maxDoc();

avdl = collectionStats.sumTotalTermFreq() / N;

if (termStats.length == 1) {
    n    = termStats[0].docFreq();
    idf_ = idf(n, N);
}
else { /* computation for a phrase */
    for (final TermStatistics stat : termStats) {
	n     = stat.docFreq();
	idf_ += idf(n, N);
    }
}

return new TFIDFWeight(collectionStats.field(), idf_, avdl);
   }