PHP simple Chinese word segmentation system (1/2)_PHP tutorial-PHP Tutorial-php.cn

PHP simple Chinese word segmentation system (1/2)_PHP tutorial

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Release： 2016-07-20 11:08:30

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PHP simple Chinese word segmentation system structure: first word hash table, Trie index tree node advantages: in word segmentation, there is no need to predict the length of the word to be queried, and it is matched word by word along the tree chain. Disadvantages: The construction and maintenance are complicated, there are many word branches, and a certain amount of space is wasted

PHP tutorial simple Chinese word segmentation system

Structure: first word hash table, trie index tree node
Advantages: word segmentation , there is no need to predict the length of the query word, and it is matched word by word along the tree chain.
Disadvantages: The construction and maintenance are complicated, there are many word branches, and a certain amount of space is wasted
* @version 0.1
* @todo constructed a general dictionary algorithm and wrote a simple word segmentation
* @author shjuto@gmail.com
* trie dictionary tree
*
*/

class trie
{
private $trie;

Function __construct()
{
$trie = array('children' => array(),'isword'=>false);
}

/**
*/ FUNCTION & Setword ($ word = '')
{
$ TrieNode = & $ this- & gt; Trie;
for ($ i = 0; $ i & lt; strlen (STRLEN $word);$i++)
                                                                                                                                                                                                                                                   through 🎜>                                                                                                             If($i == strlen($word)-1)

                                                                                                                                  $trienode = &$trienode['children'][$character];
           }


        /**
* Determine whether it is a dictionary word
*
* @param string $word
* @return bool true/false
*/
        function & isword($word)
        {
                $trienode = &$this->trie;
                for($i = 0;$i < strlen($word);$i++)
                {
                        $character = $word[$i];
                        if(!isset($trienode['children'][$character]))
                        {
                                return false;
                        }
                        else
                        {
                                //判断词结束
                                if($i == (strlen($word)-1) && $trienode['children'][$character]['isword'] == true)
                                {
                                        return true;
                                }
                                elseif($i == (strlen($word)-1) && $trienode['children'][$character]['isword'] == false)
                                {
                                        return false;
                                }
                                $trienode = &$trienode['children'][$character];
                        }
                }
        }

                                                                                                                                                               tree = $this->trie;
                            $find = array(); In AAB, you need to go back to
$ word = '';
for ($ i = 0; $ i & lt; $ TextLen; $ i ++)
{                        if(isset($trienode['children'][$text[$i]]))
                        {
                                $word = $word .$text[$i];
                                $trienode = $trienode['children'][$text[$i]];
                                if($prenode == false)
                                {
                                        $wordrootposition = $i;
                                }
                                $prenode = true;
                                if($trienode['isword'])
                                {
                                        $find[] = array('position'=>$wordrootposition,'word' =>$word);
                                }
                        }
                        else
                        {
                                $trienode = $tree;
                                $word = '';
                                if($prenode)
                                {
                                        $i = $i -1;
                                        $prenode = false;
                                }
                        }
                }
Return $find;
}
}