/** * Calculate result vector for non Conjunction query * (like '+something -another') * * @param ZSearch $reader */ private function _calculateNonConjunctionResult($reader) { if (extension_loaded('bitset')) { $required = null; $neither = bitset_empty(); $prohibited = bitset_empty(); foreach ($this->_terms as $termId => $term) { $termDocs = bitset_from_array($reader->termDocs($term)); if ($this->_signs[$termId] === true) { // required if ($required !== null) { $required = bitset_intersection($required, $termDocs); } else { $required = $termDocs; } } elseif ($this->_signs[$termId] === false) { // prohibited $prohibited = bitset_union($prohibited, $termDocs); } else { // neither required, nor prohibited $neither = bitset_union($neither, $termDocs); } $this->_termsPositions[$termId] = $reader->termPositions($term); } if ($required === null) { $required = $neither; } $this->_resVector = bitset_intersection($required, bitset_invert($prohibited, $reader->count())); } else { $required = null; $neither = array(); $prohibited = array(); foreach ($this->_terms as $termId => $term) { $termDocs = array_flip($reader->termDocs($term)); if ($this->_signs[$termId] === true) { // required if ($required !== null) { // substitute for bitset_intersection foreach ($required as $key => $value) { if (!isset($termDocs[$key])) { unset($required[$key]); } } } else { $required = $termDocs; } } elseif ($this->_signs[$termId] === false) { // prohibited // substitute for bitset_union foreach ($termDocs as $key => $value) { $prohibited[$key] = $value; } } else { // neither required, nor prohibited // substitute for bitset_union foreach ($termDocs as $key => $value) { $neither[$key] = $value; } } $this->_termsPositions[$termId] = $reader->termPositions($term); } if ($required === null) { $required = $neither; } foreach ($required as $key => $value) { if (isset($prohibited[$key])) { unset($required[$key]); } } $this->_resVector = $required; } }
/** * 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 ZSearch $reader * @return a score factor for the term */ public function idf($input, $reader) { if (!is_array($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; } }