---

ContextCountAccumulator.hpp

Go to the documentation of this file.

/*==========================================================================
 * Copyright (c) 2004 University of Massachusetts.  All Rights Reserved.
 *
 * Use of the Lemur Toolkit for Language Modeling and Information Retrieval
 * is subject to the terms of the software license set forth in the LICENSE
 * file included with this software, and also available at
 * http://www.lemurproject.org/license.html
 *
 *==========================================================================
*/


//
// ContextCountAccumulator
//
// 24 February 2004 -- tds
//

#ifndef INDRI_CONTEXTCOUNTACCUMULATOR_HPP
#define INDRI_CONTEXTCOUNTACCUMULATOR_HPP

#include "indri/ListIteratorNode.hpp"
#include "lemur-platform.h"
#include "lemur-compat.hpp"
#include <vector>
#include "indri/EvaluatorNode.hpp"
#include "indri/IndriIndex.hpp"
#include "indri/QuerySpec.hpp"
#include "indri/DocumentCount.hpp"
#include "indri/ListCache.hpp"

class ContextCountAccumulator : public EvaluatorNode {
private:
  // this is a ListIteratorNode that contains extents
  // that compose the context of the operation. _contextSize
  // is the sum of the lengths of the extents in _context.
  ListIteratorNode* _context;

  // this is a ListIteratorNode that emits an extent only for a
  // true query match; therefore _occurrences is just a simple count
  // the number of extents in _matches.
  ListIteratorNode* _matches; 

  std::string _name;
  UINT64 _occurrences;
  UINT64 _contextSize;

  UINT64 _maximumContextSize;
  UINT64 _minimumContextSize;
  UINT64 _maximumOccurrences;

  double _maximumContextFraction;

  EvaluatorNode::MResults _results;

  // cache support
  ListCache* _listCache;
  ListCache::CachedList* _cache;
  SimpleCopier _query;

public:
  ContextCountAccumulator( const std::string& name, UINT64 occurrences, UINT64 contextSize );
  ContextCountAccumulator( const std::string& name, UINT64 occurrences, UINT64 contextSize, UINT64 maximumOccurrences, UINT64 minimumContextSize, UINT64 maximumContextSize, double maximumContextFraction );
  ContextCountAccumulator( const std::string& name, ListCache* listCache, ListCache::CachedList* cache, ListIteratorNode* matches, UINT64 collectionSize, UINT64 maxDocumentLength );
  ContextCountAccumulator( const std::string& name, ListCache* listCache, ListCache::CachedList* cache, ListIteratorNode* matches, ListIteratorNode* context );

  ~ContextCountAccumulator();

  UINT64 getOccurrences() const;
  UINT64 getContextSize() const;

  const ListIteratorNode* getContextNode() const;
  const ListIteratorNode* getMatchesNode() const;
  const std::string& getName() const;

  const EvaluatorNode::MResults& getResults();
  void evaluate( int documentID, int documentLength );
  int nextCandidateDocument();
};

#endif // INDRI_CONTEXTCOUNTACCUMULATOR_HPP

---