/** * The sum of squared weights of contained query clauses. * * @return float */ public function sumOfSquaredWeights() { // compute idf $this->_idf = $this->_reader->getSimilarity()->idf($this->_query->getTerms(), $this->_reader); // compute query weight $this->_queryWeight = $this->_idf * $this->_query->getBoost(); // square it return $this->_queryWeight * $this->_queryWeight; }
/** * Return the document object for this hit * * @return \Zend\Search\Lucene\Document\Document */ public function getDocument() { if (!$this->_document instanceof Document\Document) { $this->_document = $this->_index->getDocument($this->id); } return $this->_document; }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery * @throws \Zend\Search\Lucene\Exception */ public function rewrite(Lucene\IndexInterface $index) { $this->_matches = array(); $this->_scores = array(); $this->_termKeys = array(); if ($this->_term->field === null) { // Search through all fields $fields = $index->getFieldNames(true); } else { $fields = array($this->_term->field); } $prefix = Index\Term::getPrefix($this->_term->text, $this->_prefixLength); $prefixByteLength = strlen($prefix); $prefixUtf8Length = Index\Term::getLength($prefix); $termLength = Index\Term::getLength($this->_term->text); $termRest = substr($this->_term->text, $prefixByteLength); // we calculate length of the rest in bytes since levenshtein() is not UTF-8 compatible $termRestLength = strlen($termRest); $scaleFactor = 1 / (1 - $this->_minimumSimilarity); $maxTerms = Lucene\Lucene::getTermsPerQueryLimit(); foreach ($fields as $field) { $index->resetTermsStream(); if ($prefix != '') { $index->skipTo(new Index\Term($prefix, $field)); while ($index->currentTerm() !== null && $index->currentTerm()->field == $field && substr($index->currentTerm()->text, 0, $prefixByteLength) == $prefix) { // Calculate similarity $target = substr($index->currentTerm()->text, $prefixByteLength); $maxDistance = isset($this->_maxDistances[strlen($target)]) ? $this->_maxDistances[strlen($target)] : $this->_calculateMaxDistance($prefixUtf8Length, $termRestLength, strlen($target)); if ($termRestLength == 0) { // we don't have anything to compare. That means if we just add // the letters for current term we get the new word $similarity = $prefixUtf8Length == 0 ? 0 : 1 - strlen($target) / $prefixUtf8Length; } else { if (strlen($target) == 0) { $similarity = $prefixUtf8Length == 0 ? 0 : 1 - $termRestLength / $prefixUtf8Length; } else { if ($maxDistance < abs($termRestLength - strlen($target))) { //just adding the characters of term to target or vice-versa results in too many edits //for example "pre" length is 3 and "prefixes" length is 8. We can see that //given this optimal circumstance, the edit distance cannot be less than 5. //which is 8-3 or more precisesly abs(3-8). //if our maximum edit distance is 4, then we can discard this word //without looking at it. $similarity = 0; } else { $similarity = 1 - levenshtein($termRest, $target) / ($prefixUtf8Length + min($termRestLength, strlen($target))); } } } if ($similarity > $this->_minimumSimilarity) { $this->_matches[] = $index->currentTerm(); $this->_termKeys[] = $index->currentTerm()->key(); $this->_scores[] = ($similarity - $this->_minimumSimilarity) * $scaleFactor; if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } } $index->nextTerm(); } } else { $index->skipTo(new Index\Term('', $field)); while ($index->currentTerm() !== null && $index->currentTerm()->field == $field) { // Calculate similarity $target = $index->currentTerm()->text; $maxDistance = isset($this->_maxDistances[strlen($target)]) ? $this->_maxDistances[strlen($target)] : $this->_calculateMaxDistance(0, $termRestLength, strlen($target)); if ($maxDistance < abs($termRestLength - strlen($target))) { //just adding the characters of term to target or vice-versa results in too many edits //for example "pre" length is 3 and "prefixes" length is 8. We can see that //given this optimal circumstance, the edit distance cannot be less than 5. //which is 8-3 or more precisesly abs(3-8). //if our maximum edit distance is 4, then we can discard this word //without looking at it. $similarity = 0; } else { $similarity = 1 - levenshtein($termRest, $target) / min($termRestLength, strlen($target)); } if ($similarity > $this->_minimumSimilarity) { $this->_matches[] = $index->currentTerm(); $this->_termKeys[] = $index->currentTerm()->key(); $this->_scores[] = ($similarity - $this->_minimumSimilarity) * $scaleFactor; if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } } $index->nextTerm(); } } $index->closeTermsStream(); } if (count($this->_matches) == 0) { return new EmptyResult(); } else { if (count($this->_matches) == 1) { return new Term(reset($this->_matches)); } else { $rewrittenQuery = new Boolean(); array_multisort($this->_scores, SORT_DESC, SORT_NUMERIC, $this->_termKeys, SORT_ASC, SORT_STRING, $this->_matches); $termCount = 0; foreach ($this->_matches as $id => $matchedTerm) { $subquery = new Term($matchedTerm); $subquery->setBoost($this->_scores[$id]); $rewrittenQuery->addSubquery($subquery); $termCount++; if ($termCount >= self::MAX_CLAUSE_COUNT) { break; } } return $rewrittenQuery; } } }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery */ public function rewrite(Lucene\IndexInterface $index) { // Allow to use wildcards within phrases // They are either removed by text analyzer or used as a part of keyword for keyword fields // // if (strpos($this->_phrase, '?') !== false || strpos($this->_phrase, '*') !== false) { // require_once 'Zend/Search/Lucene/Search/QueryParserException.php'; // throw new Zend_Search_Lucene_Search_QueryParserException('Wildcards are only allowed in a single terms.'); // } // Split query into subqueries if field name is not specified if ($this->_field === null) { $query = new Query\Boolean(); $query->setBoost($this->getBoost()); if (Lucene\Lucene::getDefaultSearchField() === null) { $searchFields = $index->getFieldNames(true); } else { $searchFields = array(Lucene\Lucene::getDefaultSearchField()); } foreach ($searchFields as $fieldName) { $subquery = new Phrase($this->_phrase, $this->_phraseEncoding, $fieldName); $subquery->setSlop($this->getSlop()); $query->addSubquery($subquery->rewrite($index)); } $this->_matches = $query->getQueryTerms(); return $query; } // Recognize exact term matching (it corresponds to Keyword fields stored in the index) // encoding is not used since we expect binary matching $term = new Index\Term($this->_phrase, $this->_field); if ($index->hasTerm($term)) { $query = new Query\Term($term); $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; } // tokenize phrase using current analyzer and process it as a phrase query $tokens = Analyzer\Analyzer::getDefault()->tokenize($this->_phrase, $this->_phraseEncoding); if (count($tokens) == 0) { $this->_matches = array(); return new Query\Insignificant(); } if (count($tokens) == 1) { $term = new Index\Term($tokens[0]->getTermText(), $this->_field); $query = new Query\Term($term); $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; } //It's non-trivial phrase query $position = -1; $query = new Query\Phrase(); foreach ($tokens as $token) { $position += $token->getPositionIncrement(); $term = new Index\Term($token->getTermText(), $this->_field); $query->addTerm($term, $position); $query->setSlop($this->getSlop()); } $this->_matches = $query->getQueryTerms(); return $query; }
/** * Score specified document * * @param integer $docId * @param \Zend\Search\Lucene\IndexInterface $reader * @return float */ public function score($docId, Lucene\IndexInterface $reader) { if (isset($this->_docVector[$docId])) { return $reader->getSimilarity()->tf($this->_termFreqs[$docId]) * $this->_weight->getValue() * $reader->norm($docId, $this->_term->field) * $this->getBoost(); } else { return 0; } }
/** * Score calculator for non conjunction queries (not all subqueries are required) * * @param integer $docId * @param \Zend\Search\Lucene\IndexInterface $reader * @return float */ public function _nonConjunctionScore($docId, Lucene\IndexInterface $reader) { if ($this->_coord === null) { $this->_coord = array(); $maxCoord = 0; foreach ($this->_signs as $sign) { if ($sign !== false) { $maxCoord++; } } for ($count = 0; $count <= $maxCoord; $count++) { $this->_coord[$count] = $reader->getSimilarity()->coord($count, $maxCoord); } } $score = 0; $matchedSubqueries = 0; foreach ($this->_subqueries as $subqueryId => $subquery) { $subscore = $subquery->score($docId, $reader); // Prohibited if ($this->_signs[$subqueryId] === false && $subscore != 0) { return 0; } // is required, but doen't match if ($this->_signs[$subqueryId] === true && $subscore == 0) { return 0; } if ($subscore != 0) { $matchedSubqueries++; $score += $subscore; } } return $score * $this->_coord[$matchedSubqueries] * $this->getBoost(); }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery */ public function rewrite(Lucene\IndexInterface $index) { $this->_matches = array(); if ($this->_field === null) { // Search through all fields $fields = $index->getFieldNames(true); } else { $fields = array($this->_field); } $maxTerms = Lucene\Lucene::getTermsPerQueryLimit(); foreach ($fields as $field) { $index->resetTermsStream(); if ($this->_lowerTerm !== null) { $lowerTerm = new Index\Term($this->_lowerTerm->text, $field); $index->skipTo($lowerTerm); if (!$this->_inclusive && $index->currentTerm() == $lowerTerm) { // Skip lower term $index->nextTerm(); } } else { $index->skipTo(new Index\Term('', $field)); } if ($this->_upperTerm !== null) { // Walk up to the upper term $upperTerm = new Index\Term($this->_upperTerm->text, $field); while ($index->currentTerm() !== null && $index->currentTerm()->field == $field && $index->currentTerm()->text < $upperTerm->text) { $this->_matches[] = $index->currentTerm(); if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } $index->nextTerm(); } if ($this->_inclusive && $index->currentTerm() == $upperTerm) { // Include upper term into result $this->_matches[] = $upperTerm; } } else { // Walk up to the end of field data while ($index->currentTerm() !== null && $index->currentTerm()->field == $field) { $this->_matches[] = $index->currentTerm(); if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } $index->nextTerm(); } } $index->closeTermsStream(); } if (count($this->_matches) == 0) { return new EmptyResult(); } else { if (count($this->_matches) == 1) { return new Term(reset($this->_matches)); } else { $rewrittenQuery = new MultiTerm(); foreach ($this->_matches as $matchedTerm) { $rewrittenQuery->addTerm($matchedTerm); } return $rewrittenQuery; } } }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery */ public function rewrite(Lucene\IndexInterface $index) { if ($this->_field === null) { $query = new Query\MultiTerm(); $query->setBoost($this->getBoost()); $hasInsignificantSubqueries = false; if (Lucene\Lucene::getDefaultSearchField() === null) { $searchFields = $index->getFieldNames(true); } else { $searchFields = array(Lucene\Lucene::getDefaultSearchField()); } foreach ($searchFields as $fieldName) { $subquery = new Term($this->_word, $this->_encoding, $fieldName); $rewrittenSubquery = $subquery->rewrite($index); foreach ($rewrittenSubquery->getQueryTerms() as $term) { $query->addTerm($term); } if ($rewrittenSubquery instanceof Query\Insignificant) { $hasInsignificantSubqueries = true; } } if (count($query->getTerms()) == 0) { $this->_matches = array(); if ($hasInsignificantSubqueries) { return new Query\Insignificant(); } else { return new Query\EmptyResult(); } } $this->_matches = $query->getQueryTerms(); return $query; } // ------------------------------------- // Recognize exact term matching (it corresponds to Keyword fields stored in the index) // encoding is not used since we expect binary matching $term = new Index\Term($this->_word, $this->_field); if ($index->hasTerm($term)) { $query = new Query\Term($term); $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; } // ------------------------------------- // Recognize wildcard queries /** @todo check for PCRE unicode support may be performed through Zend_Environment in some future */ if (@preg_match('/\\pL/u', 'a') == 1) { $word = iconv($this->_encoding, 'UTF-8', $this->_word); $wildcardsPattern = '/[*?]/u'; $subPatternsEncoding = 'UTF-8'; } else { $word = $this->_word; $wildcardsPattern = '/[*?]/'; $subPatternsEncoding = $this->_encoding; } $subPatterns = preg_split($wildcardsPattern, $word, -1, PREG_SPLIT_OFFSET_CAPTURE); if (count($subPatterns) > 1) { // Wildcard query is recognized $pattern = ''; foreach ($subPatterns as $id => $subPattern) { // Append corresponding wildcard character to the pattern before each sub-pattern (except first) if ($id != 0) { $pattern .= $word[$subPattern[1] - 1]; } // Check if each subputtern is a single word in terms of current analyzer $tokens = Analyzer\Analyzer::getDefault()->tokenize($subPattern[0], $subPatternsEncoding); if (count($tokens) > 1) { throw new QueryParserException('Wildcard search is supported only for non-multiple word terms'); } foreach ($tokens as $token) { $pattern .= $token->getTermText(); } } $term = new Index\Term($pattern, $this->_field); $query = new Query\Wildcard($term); $query->setBoost($this->getBoost()); // Get rewritten query. Important! It also fills terms matching container. $rewrittenQuery = $query->rewrite($index); $this->_matches = $query->getQueryTerms(); return $rewrittenQuery; } // ------------------------------------- // Recognize one-term multi-term and "insignificant" queries $tokens = Analyzer\Analyzer::getDefault()->tokenize($this->_word, $this->_encoding); if (count($tokens) == 0) { $this->_matches = array(); return new Query\Insignificant(); } if (count($tokens) == 1) { $term = new Index\Term($tokens[0]->getTermText(), $this->_field); $query = new Query\Term($term); $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; } //It's not insignificant or one term query $query = new Query\MultiTerm(); /** * @todo Process $token->getPositionIncrement() to support stemming, synonyms and other * analizer design features */ foreach ($tokens as $token) { $term = new Index\Term($token->getTermText(), $this->_field); $query->addTerm($term, true); // all subterms are required } $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery * @throws \Zend\Search\Lucene\Exception */ public function rewrite(Lucene\IndexInterface $index) { $this->_matches = array(); if ($this->_pattern->field === null) { // Search through all fields $fields = $index->getFieldNames(true); } else { $fields = array($this->_pattern->field); } $prefix = self::_getPrefix($this->_pattern->text); $prefixLength = strlen($prefix); $matchExpression = '/^' . str_replace(array('\\?', '\\*'), array('.', '.*'), preg_quote($this->_pattern->text, '/')) . '$/'; if ($prefixLength < self::$_minPrefixLength) { throw new Lucene\Exception('At least ' . self::$_minPrefixLength . ' non-wildcard characters are required at the beginning of pattern.'); } /** @todo check for PCRE unicode support may be performed through Zend_Environment in some future */ if (@preg_match('/\\pL/u', 'a') == 1) { // PCRE unicode support is turned on // add Unicode modifier to the match expression $matchExpression .= 'u'; } $maxTerms = Lucene\Lucene::getTermsPerQueryLimit(); foreach ($fields as $field) { $index->resetTermsStream(); if ($prefix != '') { $index->skipTo(new Index\Term($prefix, $field)); while ($index->currentTerm() !== null && $index->currentTerm()->field == $field && substr($index->currentTerm()->text, 0, $prefixLength) == $prefix) { if (preg_match($matchExpression, $index->currentTerm()->text) === 1) { $this->_matches[] = $index->currentTerm(); if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } } $index->nextTerm(); } } else { $index->skipTo(new Index\Term('', $field)); while ($index->currentTerm() !== null && $index->currentTerm()->field == $field) { if (preg_match($matchExpression, $index->currentTerm()->text) === 1) { $this->_matches[] = $index->currentTerm(); if ($maxTerms != 0 && count($this->_matches) > $maxTerms) { throw new Lucene\Exception('Terms per query limit is reached.'); } } $index->nextTerm(); } } $index->closeTermsStream(); } if (count($this->_matches) == 0) { return new EmptyResult(); } else { if (count($this->_matches) == 1) { return new Term(reset($this->_matches)); } else { $rewrittenQuery = new MultiTerm(); foreach ($this->_matches as $matchedTerm) { $rewrittenQuery->addTerm($matchedTerm); } return $rewrittenQuery; } } }
/** * Execute query in context of index reader * It also initializes necessary internal structures * * @param \Zend\Search\Lucene\IndexInterface $reader * @param \Zend\Search\Lucene\Index\DocsFilter|null $docsFilter */ public function execute(Lucene\IndexInterface $reader, $docsFilter = null) { $this->_resVector = null; if (count($this->_terms) == 0) { $this->_resVector = array(); } $resVectors = array(); $resVectorsSizes = array(); $resVectorsIds = array(); // is used to prevent arrays comparison foreach ($this->_terms as $termId => $term) { $resVectors[] = array_flip($reader->termDocs($term)); $resVectorsSizes[] = count(end($resVectors)); $resVectorsIds[] = $termId; $this->_termsPositions[$termId] = $reader->termPositions($term); } // sort resvectors in order of subquery cardinality increasing array_multisort($resVectorsSizes, SORT_ASC, SORT_NUMERIC, $resVectorsIds, SORT_ASC, SORT_NUMERIC, $resVectors); foreach ($resVectors as $nextResVector) { if ($this->_resVector === null) { $this->_resVector = $nextResVector; } else { //$this->_resVector = array_intersect_key($this->_resVector, $nextResVector); /** * This code is used as workaround for array_intersect_key() slowness problem. */ $updatedVector = array(); foreach ($this->_resVector as $id => $value) { if (isset($nextResVector[$id])) { $updatedVector[$id] = $value; } } $this->_resVector = $updatedVector; } if (count($this->_resVector) == 0) { // Empty result set, we don't need to check other terms break; } } // ksort($this->_resVector, SORT_NUMERIC); // Docs are returned ordered. Used algorithm doesn't change elements order. // Initialize weight if it's not done yet $this->_initWeight($reader); }
/** * Computes a score factor for a simple term or a phrase. * * The default implementation is: * return idfFreq(searcher.docFreq(term), searcher.maxDoc()); * * input - the term in question or array of terms * reader - reader the document collection being searched * Returns a score factor for the term * * @param mixed $input * @param \Zend\Search\Lucene\IndexInterface $reader * @return a score factor for the term */ public function idf($input, \Zend\Search\Lucene\IndexInterface $reader) { if (!is_array($input)) { return $this->idfFreq($reader->docFreq($input), $reader->count()); } else { $idf = 0.0; foreach ($input as $term) { $idf += $this->idfFreq($reader->docFreq($term), $reader->count()); } return $idf; } }
/** * Score calculator for non conjunction queries (not all terms are required) * * @param integer $docId * @param \Zend\Search\Lucene\IndexInterface $reader * @return float */ public function _nonConjunctionScore($docId, $reader) { if ($this->_coord === null) { $this->_coord = array(); $maxCoord = 0; foreach ($this->_signs as $sign) { if ($sign !== false) { $maxCoord++; } } for ($count = 0; $count <= $maxCoord; $count++) { $this->_coord[$count] = $reader->getSimilarity()->coord($count, $maxCoord); } } $score = 0.0; $matchedTerms = 0; foreach ($this->_terms as $termId => $term) { // Check if term is if ($this->_signs[$termId] !== false && isset($this->_termsFreqs[$termId][$docId])) { $matchedTerms++; /** * We don't need to check that term freq is not 0 * Score calculation is performed only for matched docs */ $score += $reader->getSimilarity()->tf($this->_termsFreqs[$termId][$docId]) * $this->_weights[$termId]->getValue() * $reader->norm($docId, $term->field); } } return $score * $this->_coord[$matchedTerms] * $this->getBoost(); }
/** * Re-write query into primitive queries in the context of specified index * * @param \Zend\Search\Lucene\IndexInterface $index * @return \Zend\Search\Lucene\Search\Query\AbstractQuery */ public function rewrite(Lucene\IndexInterface $index) { if ($this->_field === null) { $query = new Search\Query\Boolean(); $hasInsignificantSubqueries = false; if (Lucene\Lucene::getDefaultSearchField() === null) { $searchFields = $index->getFieldNames(true); } else { $searchFields = array(Lucene\Lucene::getDefaultSearchField()); } foreach ($searchFields as $fieldName) { $subquery = new self($this->_word, $this->_encoding, $fieldName, $this->_minimumSimilarity); $rewrittenSubquery = $subquery->rewrite($index); if (!($rewrittenSubquery instanceof Query\Insignificant || $rewrittenSubquery instanceof Query\EmptyResult)) { $query->addSubquery($rewrittenSubquery); } if ($rewrittenSubquery instanceof Query\Insignificant) { $hasInsignificantSubqueries = true; } } $subqueries = $query->getSubqueries(); if (count($subqueries) == 0) { $this->_matches = array(); if ($hasInsignificantSubqueries) { return new Query\Insignificant(); } else { return new Query\EmptyResult(); } } if (count($subqueries) == 1) { $query = reset($subqueries); } $query->setBoost($this->getBoost()); $this->_matches = $query->getQueryTerms(); return $query; } // ------------------------------------- // Recognize exact term matching (it corresponds to Keyword fields stored in the index) // encoding is not used since we expect binary matching $term = new Index\Term($this->_word, $this->_field); if ($index->hasTerm($term)) { $query = new Query\Fuzzy($term, $this->_minimumSimilarity); $query->setBoost($this->getBoost()); // Get rewritten query. Important! It also fills terms matching container. $rewrittenQuery = $query->rewrite($index); $this->_matches = $query->getQueryTerms(); return $rewrittenQuery; } // ------------------------------------- // Recognize wildcard queries /** @todo check for PCRE unicode support may be performed through Zend_Environment in some future */ if (@preg_match('/\\pL/u', 'a') == 1) { $subPatterns = preg_split('/[*?]/u', iconv($this->_encoding, 'UTF-8', $this->_word)); } else { $subPatterns = preg_split('/[*?]/', $this->_word); } if (count($subPatterns) > 1) { throw new Search\QueryParserException('Fuzzy search doesn\'t support wildcards (except within Keyword fields).'); } // ------------------------------------- // Recognize one-term multi-term and "insignificant" queries $tokens = Analyzer\Analyzer::getDefault()->tokenize($this->_word, $this->_encoding); if (count($tokens) == 0) { $this->_matches = array(); return new Query\Insignificant(); } if (count($tokens) == 1) { $term = new Index\Term($tokens[0]->getTermText(), $this->_field); $query = new Query\Fuzzy($term, $this->_minimumSimilarity); $query->setBoost($this->getBoost()); // Get rewritten query. Important! It also fills terms matching container. $rewrittenQuery = $query->rewrite($index); $this->_matches = $query->getQueryTerms(); return $rewrittenQuery; } // Word is tokenized into several tokens throw new Search\QueryParserException('Fuzzy search is supported only for non-multiple word terms'); }