Subversion-Projekte lars-tiefland.prado

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Revision Autor Zeilennr. Zeile
1 lars 1 
<?php
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/**
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 * Zend Framework
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 *
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 * LICENSE
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 *
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 * This source file is subject to version 1.0 of the Zend Framework
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 * license, that is bundled with this package in the file LICENSE, and
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 * is available through the world-wide-web at the following URL:
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 * http://www.zend.com/license/framework/1_0.txt. If you did not receive
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 * a copy of the Zend Framework license and are unable to obtain it
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 * through the world-wide-web, please send a note to license@zend.com
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 * so we can mail you a copy immediately.
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 *
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 * @package    Zend_Search_Lucene
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 * @subpackage Search
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 * @copyright  Copyright (c) 2005-2006 Zend Technologies USA Inc. (http://www.zend.com)
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 * @license    http://www.zend.com/license/framework/1_0.txt Zend Framework License version 1.0
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 */
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/**
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 * @package    Zend_Search_Lucene
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 * @subpackage Search
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 * @copyright  Copyright (c) 2005-2006 Zend Technologies USA Inc. (http://www.zend.com)
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 * @license    http://www.zend.com/license/framework/1_0.txt Zend Framework License version 1.0
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 */
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class Zend_Search_Lucene_Search_Similarity_Default extends Zend_Search_Lucene_Search_Similarity
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{
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    /**
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     * Implemented as '1/sqrt(numTerms)'.
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     *
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     * @param string $fieldName
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     * @param integer numTerms
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     * @return float
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     */
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    public function lengthNorm($fieldName, $numTerms)
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    {
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        return 1.0/sqrt($numTerms);
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    }
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    /**
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     * Implemented as '1/sqrt(sumOfSquaredWeights)'.
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     *
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     * @param float $sumOfSquaredWeights
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     * @return float
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     */
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    public function queryNorm($sumOfSquaredWeights)
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    {
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        return 1.0/sqrt($sumOfSquaredWeights);
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    }
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    /**
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     * Implemented as 'sqrt(freq)'.
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     *
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     * @param float $freq
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     * @return float
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     */
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    public function tf($freq)
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    {
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        return sqrt($freq);
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    }
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    /**
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     * Implemented as '1/(distance + 1)'.
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     *
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     * @param integer $distance
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     * @return float
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     */
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    public function sloppyFreq($distance)
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    {
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        return 1.0/($distance + 1);
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    }
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    /**
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     * Implemented as 'log(numDocs/(docFreq+1)) + 1'.
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     *
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     * @param integer $docFreq
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     * @param integer $numDocs
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     * @return float
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     */
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    public function idfFreq($docFreq, $numDocs)
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    {
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        return log($numDocs/(float)($docFreq+1)) + 1.0;
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    }
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    /**
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     * Implemented as 'overlap/maxOverlap'.
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     *
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     * @param integer $overlap
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     * @param integer $maxOverlap
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     * @return float
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     */
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    public function coord($overlap, $maxOverlap)
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    {
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        return $overlap/(float)$maxOverlap;
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    }
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}