summaryrefslogtreecommitdiff
path: root/demos/quickstart/protected/index/Zend/Search/Lucene/Search/Weight/MultiTerm.php
blob: 69528ba4fcb29c2a5134c337ba43197a384c9797 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to version 1.0 of the Zend Framework
 * license, that is bundled with this package in the file LICENSE, and
 * is available through the world-wide-web at the following URL:
 * http://www.zend.com/license/framework/1_0.txt. If you did not receive
 * a copy of the Zend Framework license and are unable to obtain it
 * through the world-wide-web, please send a note to license@zend.com
 * so we can mail you a copy immediately.
 *
 * @package    Zend_Search_Lucene
 * @subpackage Search
 * @copyright  Copyright (c) 2005-2006 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://www.zend.com/license/framework/1_0.txt Zend Framework License version 1.0
 */


/** Zend_Search_Lucene_Search_Weight */
require_once 'Zend/Search/Lucene/Search/Weight.php';


/**
 * @package    Zend_Search_Lucene
 * @subpackage Search
 * @copyright  Copyright (c) 2005-2006 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://www.zend.com/license/framework/1_0.txt Zend Framework License version 1.0
 */
class Zend_Search_Lucene_Search_Weight_MultiTerm extends Zend_Search_Lucene_Search_Weight
{
    /**
     * IndexReader.
     *
     * @var Zend_Search_Lucene
     */
    private $_reader;

    /**
     * The query that this concerns.
     *
     * @var Zend_Search_Lucene_Search_Query_MultiTerm
     */
    private $_query;

    /**
     * Query terms weights
     * Array of Zend_Search_Lucene_Search_Weight_Term
     *
     * @var array
     */
    private $_weights;


    /**
     * Zend_Search_Lucene_Search_Weight_MultiTerm constructor
     * query - the query that this concerns.
     * reader - index reader
     *
     * @param Zend_Search_Lucene_Search_Query_MultiTerm $query
     * @param Zend_Search_Lucene $reader
     */
    public function __construct($query, $reader)
    {
        $this->_query   = $query;
        $this->_reader  = $reader;
        $this->_weights = array();

        $signs = $query->getSigns();

        foreach ($query->getTerms() as $num => $term) {
            if ($signs === null || $signs[$num] === null || $signs[$num]) {
                $this->_weights[$num] = new Zend_Search_Lucene_Search_Weight_Term($term, $query, $reader);
                $query->setWeight($num, $this->_weights[$num]);
            }
        }
    }


    /**
     * The weight for this query
     *
     * @return float
     */
    public function getValue()
    {
        return $this->_query->getBoost();
    }


    /**
     * The sum of squared weights of contained query clauses.
     *
     * @return float
     */
    public function sumOfSquaredWeights()
    {
        $sum = 0;
        foreach ($this->_weights as $weight) {
            // sum sub weights
            $sum += $weight->sumOfSquaredWeights();
        }

        // boost each sub-weight
        $sum *= $this->_query->getBoost() * $this->_query->getBoost();

        // check for empty query (like '-something -another')
        if ($sum == 0) {
            $sum = 1.0;
        }
        return $sum;
    }


    /**
     * Assigns the query normalization factor to this.
     *
     * @param float $queryNorm
     */
    public function normalize($queryNorm)
    {
        // incorporate boost
        $queryNorm *= $this->_query->getBoost();

        foreach ($this->_weights as $weight) {
            $weight->normalize($queryNorm);
        }
    }
}