PHP functions extract keywords from a text string

This article mainly introduces how PHP functions extract keywords from a text string, involving php's string traversal and search operations. For more information, see

This article mainly introduces how PHP functions extract keywords from a text string, involving php's string traversal and search operations. For more information, see

This example describes how PHP functions extract keywords from a text string. Share it with you for your reference. The specific analysis is as follows:

This is a function positioning receives a string as a parameter (along with other configuration optional parameters), and locates all the keywords in the string (the most frequently used word ),, returns an array or a string of keywords separated by commas. The function works normally, but I am improving it. Therefore, if you are interested, you can raise suggestions for improvement.

/*** Finds all of the keywords (words that appear most) on param $ str * and return them in order of most occurrences to less occurrences. * @ param string $ str The string to search for the keywords. * @ param int $ minWordLen [optional] The minimun length (number of chars) of a word to be considered a keyword. * @ param int $ minWordOccurrences [optional] The minimun number of times a word has to appear * On param $ str to be considered a keyword. * @ param boolean $ asArray [optional] Specifies if the function returns a string with the * keywords separated by a comma ($ asArray = false) or a keywords array ($ asArray = true ). * @ return mixed A string with keywords separated with commas if param $ asArray is true, * an array with the keywords otherwise. */function extract_keywords ($ str, $ minWordLen = 3, $ MinWordOccurrences = 2, $ asArray = false) {function keyword_count_sort ($ first, $ sec) {return $ sec [1]-$ first [1];} $ str = preg_replace ('/[^ \ w0-9]/', '', $ str); $ str = trim (preg_replace ('/\ s + /', '', $ str); $ words = explode ('', $ str); $ keywords = array (); while ($ c_word = array_shift ($ words ))! = Null) {if (strlen ($ c_word) <= $ minWordLen) continue; $ c_word = strtolower ($ c_word); if (array_key_exists ($ c_word, $ keywords )) $ keywords [$ c_word] [1] ++; else $ keywords [$ c_word] = array ($ c_word, 1) ;}usort ($ keywords, 'keyword _ count_sort '); $ final_keywords = array (); foreach ($ keywords as $ keyword_det) {if ($ keyword_det [1] <$ minWordOccurrences) break; array_push ($ final_keywords, $ keyword_det [0]);} return $ AsArray? $ Final_keywords: implode (',', $ final_keywords);} // How to use // Basic lorem ipsum text to extract the keywords $ text = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. curabitur eget ipsum ut lorem laoreet porta a non libero. vivamus in tortor metus. suspendisse potenti. curabitur metus nisi, adipiscing eget placerat suscipit, suscipit vitae felis. integer eu odio enim, sed dignissim lorem. in fringilla molestie justo, vitae varius risus lacinia ac. nulla porttitor justo a lectus iaculis ut vestibulum magna egestas. ut sed purus et nibh cursus fringilla at id purus. "; // Echoes: lorem, suscipit, metus, fringilla, purus, justo, eget, vitae, ipsum, curabitur, adipiscingecho extract_keywords ($ text );

I hope this article will help you with php programming.