void indri::index::MemoryIndex::_writeFieldExtents( lemur::api::DOCID_T documentID, indri::utility::greedy_vector<indri::parse::TagExtent *>& indexedTags ) { indri::utility::HashTable< indri::parse::TagExtent *, int> tagIdMap; // sort fields std::sort( indexedTags.begin(), indexedTags.end(), indri::parse::LessTagExtent() ); // we'll add to the end of the fields greedy_vector indri::utility::greedy_vector<indri::index::FieldExtent> & fields = _termList.fields(); // this is used to set the parentOrdinals int offset = fields.size(); // convert to field extents, set ids, and create the node map for( size_t i=0; i<indexedTags.size(); i++ ) { indri::parse::TagExtent * extent = indexedTags[i]; int ordinal = int(i) + 1; // this is the id for the field type int tagId = _fieldID( extent->name ); // convert the field indri::index::FieldExtent converted( tagId, extent->begin, extent->end, extent->number, ordinal); // add this node to the map; tagIdMap.insert( extent, ordinal ); // add his field to the field list for the document fields.push_back( converted ); // add this location to the inverted list for fields - deferred to below - // _fieldLists[tagId - 1]->addLocation( documentID, extent->begin, extent->end, extent->number, ordinal ); } // set the parent ordinals for( size_t j=0; j<indexedTags.size(); j++ ) { indri::parse::TagExtent * extent = indexedTags[j]; // look up the parent int parentOrdinal = 0; int * parentIter; if ( extent->parent != 0 ) { parentIter = tagIdMap.find( extent->parent ); if( parentIter != 0 ) { parentOrdinal = *parentIter; } else { parentOrdinal = 0; } } // set the parent int ordinal = fields[ offset + j ].ordinal; int tagId = fields[ offset + j ].id; fields[ offset + j ].parentOrdinal = parentOrdinal; // add this location to the inverted list for fields _fieldLists[tagId - 1]->addLocation( documentID, extent->begin, extent->end, extent->number, ordinal, parentOrdinal ); } }
void indri::infnet::ExtentAndNode::_and( indri::utility::greedy_vector<indri::index::Extent>& out, const indri::utility::greedy_vector<indri::index::Extent>& one, const indri::utility::greedy_vector<indri::index::Extent>& two ) { indri::utility::greedy_vector<indri::index::Extent>::const_iterator oneIter = one.begin(); indri::utility::greedy_vector<indri::index::Extent>::const_iterator twoIter = two.begin(); out.clear(); indri::index::Extent current; current.begin = 0; current.end = 0; while( oneIter != one.end() && twoIter != two.end() ) { indri::index::Extent intersection; // compute the intersection (may be 0 length) intersection.begin = lemur_compat::max( oneIter->begin, twoIter->begin ); intersection.end = lemur_compat::min( oneIter->end, twoIter->end ); intersection.begin = lemur_compat::min( intersection.begin, intersection.end ); if( current.end < intersection.begin ) { // if last intersection had non-zero length, put it out in the vector if( current.begin < current.end ) out.push_back( current ); current = intersection; } else { // this intersection touches the last intersection, // so we'll just put them together current.end = intersection.end; } if( oneIter->end == intersection.end ) { oneIter++; } if( twoIter->end == intersection.end ) { twoIter++; } } if( current.begin != current.end ) _extents.push_back( current ); }
void IndexWriter::_writeStatistics( indri::utility::greedy_vector<WriterIndexContext*>& lists, indri::index::TermData* termData, UINT64& startOffset ) { indri::utility::greedy_vector<WriterIndexContext*>::iterator iter; ::termdata_clear( termData, _fields.size() ); // find out what term we're writing strcpy( const_cast<char*>(termData->term), lists[0]->iterator->currentEntry()->termData->term ); for( iter = lists.begin(); iter != lists.end(); ++iter ) { indri::index::DocListFileIterator::DocListData* listData = (*iter)->iterator->currentEntry(); ::termdata_merge( termData, listData->termData, _fields.size() ); } _termDataBuffer.clear(); indri::utility::RVLCompressStream stream( _termDataBuffer ); stream << termData->term; ::termdata_compress( stream, termData, _fields.size() ); startOffset = _invertedOutput->tell(); int dataSize = stream.dataSize(); _invertedOutput->write( &dataSize, sizeof(UINT32) ); _invertedOutput->write( stream.data(), stream.dataSize() ); }
void IndexWriter::_addInvertedListData( indri::utility::greedy_vector<WriterIndexContext*>& lists, indri::index::TermData* termData, indri::utility::Buffer& listBuffer, UINT64& endOffset ) { indri::utility::greedy_vector<WriterIndexContext*>::iterator iter; const int minimumSkip = 1<<12; // 4k int documentsWritten = 0; const float topdocsFraction = 0.01f; bool hasTopdocs = termData->corpus.documentCount > TOPDOCS_DOCUMENT_COUNT; bool isFrequent = termData->corpus.totalCount > FREQUENT_TERM_COUNT; int topdocsCount = hasTopdocs ? int(termData->corpus.documentCount * 0.01) : 0; int topdocsSpace = hasTopdocs ? ((topdocsCount*3*sizeof(UINT32)) + sizeof(int)) : 0; // write a control byte char control = (hasTopdocs ? 0x01 : 0) | (isFrequent ? 0x02 : 0); _invertedOutput->write( &control, 1 ); UINT64 initialPosition = _invertedOutput->tell(); // leave some room for the topdocs list if( hasTopdocs ) { _invertedOutput->seek( topdocsSpace + initialPosition ); } // maintain a list of top documents std::priority_queue<DocListIterator::TopDocument, std::vector<DocListIterator::TopDocument>, DocListIterator::TopDocument::greater> topdocs; double threshold = 0; int lastDocument = 0; int positions = 0; int docs = 0; // for each matching list: for( iter = lists.begin(); iter != lists.end(); ++iter ) { indri::index::DocListFileIterator::DocListData* listData = (*iter)->iterator->currentEntry(); DocListIterator* iterator = listData->iterator; Index* index = (*iter)->index; indri::utility::RVLCompressStream stream( listBuffer ); int listDocs = 0; int listPositions = 0; while( !iterator->finished() ) { // get the latest entry from the list DocListIterator::DocumentData* documentData = iterator->currentEntry(); // add to document counter docs++; listDocs++; // update the topdocs list if( hasTopdocs ) { int length = index->documentLength( documentData->document ); int count = documentData->positions.size(); // compute DocListIterator::TopDocument::greater (current, top()) // if false, no reason to insert this entry. // note that the test is inverted. // int(length * threshold) <= count is equivalent to // count/length > topdocs.top().count/topdocs.top().length // but we use < to force breaking a tie in favor of keeping // the first seen document. if( int(length * threshold) < count || topdocs.size() < topdocsCount ) { // form a topdocs entry for this document DocListIterator::TopDocument topDocument( documentData->document, count, length ); topdocs.push( topDocument ); while( topdocs.size() > topdocsCount ) topdocs.pop(); threshold = topdocs.top().count / double(topdocs.top().length); } } if( listBuffer.position() > minimumSkip ) { // time to write in a skip _writeBatch( _invertedOutput, documentData->document, listBuffer.position(), listBuffer ); // delta encode documents by batch lastDocument = 0; } assert( documentData->document > lastDocument ); // write this entry out to the list stream << documentData->document - lastDocument; stream << (int) documentData->positions.size(); lastDocument = documentData->document; int lastPosition = 0; for( int i=0; i<documentData->positions.size(); i++ ) { stream << (documentData->positions[i] - lastPosition); lastPosition = documentData->positions[i]; positions++; listPositions++; } iterator->nextEntry(); } indri::index::TermData* td = iterator->termData(); assert( listPositions == td->corpus.totalCount ); assert( listDocs == td->corpus.documentCount ); } assert( docs == termData->corpus.documentCount ); assert( positions == termData->corpus.totalCount ); // write in the final skip info _writeBatch( _invertedOutput, -1, listBuffer.position(), listBuffer ); UINT64 finalPosition = _invertedOutput->tell(); if( hasTopdocs ) { _invertedOutput->seek( initialPosition ); _invertedOutput->write( &topdocsCount, sizeof(int) ); assert( topdocs.size() == topdocsCount ); // write these into the topdocs list in order from smallest fraction to largest fraction, // where fraction = c(w;D)/|D| while( topdocs.size() ) { DocListIterator::TopDocument topDocument = topdocs.top(); _invertedOutput->write( &topDocument.document, sizeof(int) ); _invertedOutput->write( &topDocument.count, sizeof(int) ); _invertedOutput->write( &topDocument.length, sizeof(int) ); topdocs.pop(); } assert( (_invertedOutput->tell() - initialPosition) == topdocsSpace ); _invertedOutput->seek( finalPosition ); } endOffset = finalPosition; }