// ** Films::similarTo
SimilarFilmsArray Films::similarTo( const std::string& oid, int count ) const
{
SimilarFilmsArray result;
OID objectId = OID( oid );
CollectionPtr similars = m_target->collection( "similar" );
CursorPtr cursor = similars->find( QUERY( "$or" << ARRAY( DOCUMENT( "first" << oid ) << DOCUMENT( "second" << objectId ) ) ) );
DocumentPtr document;
while( (document = cursor->next()) ) {
// ** Read data from document
OID first = document->objectId( "first" );
OID second = document->objectId( "second" );
int value = document->integer( "value" );
// ** Decode similarity & accuracy
float similarity, accuracy;
decodeSimilarity( value, similarity, accuracy );
// ** Push similar film
Film film = filmById( first == objectId ? second : first );
Quality quality = qualityFromRange( similarity, m_similarityQuartiles );
result.push_back( SimilarFilm( film, similarity, accuracy, quality ) );
}
std::sort( result.begin(), result.end(), SimilarFilm::sortBySimilarity );
if( count ) {
result.resize( std::min( count, ( int )result.size() ) );
}
return result;
}
// ** Films::processFilms
void Films::processFilms( float sharedThreshold )
{
CursorPtr films = m_source->collection( "items" )->find();
CollectionPtr processed = m_target->collection( "items" );
CollectionPtr similar = m_target->collection( "similar" );
IRecommenderItems* items = new StreamedFilms( *this, m_target );
SimilarityPtr similarity = SimilarityPtr( new JaccardAccuracySimilarity( NumericFeatures::pearson, 0.0f, 0.0f, sharedThreshold ) );
Recommender recommender = Recommender( this, similarity.get() );
DocumentPtr document;
int counter = 0;
int total = m_source->collection( "items" )->count();
while( (document = films->next()) ) {
// ** Read the item id
int itemId = document->integer( "itemId" );
// ** Print progress
if( (++counter % 10) == 0 ) printf( "Processing films [%d/%d]\n", counter, total );
// ** Skip processed films
if( processed->findOne( QUERY( "itemId" << itemId ) ) != NULL ) {
continue;
}
// ** Load first item
items->first();
// ** Compute and store similarities
RecommenderItem item = findById( itemId );
SimilarItems pairs = recommender.findSimilarItems( items, &item );
OID oid = filmIdToObjectId( itemId );
for( SimilarItems::const_iterator i = pairs.begin(), end = pairs.end(); i != end; ++i ) {
similar->insert( DOCUMENT( "first" << oid << "second" << filmIdToObjectId( i->m_item ) << "value" << ( int )encodeSimilarity( i->m_similarity, i->m_shared ) ) );
}
// ** Store processed film
processed->insert( DOCUMENT( "itemId" << itemId ) );
}
// ** Build indices
similar->ensureIndex( "idxFirst", DOCUMENT( "first" << 1 ) );
similar->ensureIndex( "idxSecond", DOCUMENT( "second" << 1 ) );
// ** Delete iterator
delete items;
}
// ** Films::objectIdToFilmId
int Films::objectIdToFilmId( const OID& oid ) const
{
int result = -1;
CollectionPtr items = m_source->collection( "items" );
DocumentPtr item = items->findOne( QUERY( "_id" << oid ) );
assert( item != NULL );
if( item != NULL ) {
result = item->integer( "itemId" );
}
return result;
}
// ** PreloadedFilms::PreloadedFilms
PreloadedFilms::PreloadedFilms( const Films& films, const CursorPtr& cursor )
{
do {
DocumentPtr document = cursor->next();
if( document == NULL ) {
break;
}
RecommenderItem* item = new RecommenderItem;
item->m_userData = new OID( *document->_id().value() );
item->m_id = document->integer( "itemId" );
item->m_name = document->string( "name.ru" );
item->m_featureSpaces["votes"] = films.votesForFilm( item->m_id );
m_items[item->m_id] = item;
} while( true );
}
// ** Films::updateVotesCount
void Films::updateVotesCount( void )
{
CollectionPtr items = m_source->collection( "items" );
CollectionPtr votes = m_source->collection( "votes" );
CursorPtr cursor = items->find();
DocumentPtr document;
IntegerSamples samples;
int progress = 0;
int total = items->count();
while( (document = cursor->next()) ) {
int itemId = document->integer( "itemId" );
int count = votes->count( QUERY( "itemId" << itemId ) );
items->update( QUERY( "itemId" << itemId ), DOCUMENT( "$set" << DOCUMENT( "votesCount" << count ) ) );
printf( "Updating votes count [%d/%d]...\n", ++progress, total );
}
}
// ** Films::showStats
void Films::showStats( void ) const
{
CollectionPtr items = m_source->collection( "items" );
CursorPtr cursor = items->find();
DocumentPtr document;
IntegerSamples countSamples;
while( (document = cursor->next()) ) {
countSamples += document->integer( "votesCount" );
}
IntegerArray quartiles = countSamples.quartiles();
printf( "Votes: min %d, max %d, average amount %d, medean %d, quartiles %d/%d/%d\n", countSamples.min(), countSamples.max(), countSamples.mean(), countSamples.median(), quartiles[0], quartiles[1], quartiles[2] );
for( int i = 2; i <= 7; i++ ) {
int amount = pow( 10, i );
printf( "%d items has greater than %d votes\n", countSamples.greaterCount( amount ), amount );
}
}
// ** Films::votesForFilm
NumericFeatures Films::votesForFilm( int filmId ) const
{
NumericFeatures result;
CollectionPtr votes = m_source->collection( "votes" );
CursorPtr cursor = votes->find( QUERY( "itemId" << filmId ) );
DocumentPtr document;
while( (document = cursor->next()) ) {
printf( "get\n" );
result.set( document->integer( "userId" ), document->number( "rating" ) );
printf( "v %d\n", result.size() );
// sleep(1);
printf( "next\n" );
}
printf( "done! %d\n", result.size() );
return result;
}
// ** Films::updateSharedAndSimilarityRanges
void Films::updateSharedAndSimilarityRanges( void )
{
CollectionPtr similar = m_target->collection( "similar" );
CursorPtr cursor = similar->find();
int count = similar->count();
int progress = 0;
DocumentPtr document;
FloatSamples similaritySamples, sharedSamples;
while( (document = cursor->next()) ) {
float similarity, shared;
decodeSimilarity( document->integer( "value" ), similarity, shared );
similaritySamples += similarity;
sharedSamples += shared;
if( (++progress % 1000) == 0 ) printf( "Updating ranges [%d/%d]\n", progress, count );
}
m_target->collection( "info" )->upsert( QUERY( "type" << "similarity" ), DOCUMENT( "type" << "similarity" << "shared" << sharedSamples.quartiles() << "similarity" << similaritySamples.quartiles() ) );
}
// ** StreamedFilms::documentToItem
void StreamedFilms::documentToItem( RecommenderItem& item, const DocumentPtr& document ) const
{
item.m_id = document->integer( "itemId" );
item.m_featureSpaces["votes"] = m_films.votesForFilm( item.m_id );
}
// ** Films::filmFromDocument
Film Films::filmFromDocument( const DocumentPtr& document ) const
{
Film film( document->_id(), document->string( "name.ru" ), document->integerSet( "genres" ), document->integer( "year" ) );
film.m_video = document->string( "video" );
return film;
}
