metaphone

(PHP 4, PHP 5)

metaphone — Calculate the metaphone key of a string

说明

string metaphone ( string $str [, int $phonemes = 0 ] )

Calculates the metaphone key of str.

Similar to soundex() metaphone creates the same key for similar sounding words. It's more accurate than soundex() as it knows the basic rules of English pronunciation. The metaphone generated keys are of variable length.

Metaphone was developed by Lawrence Philips <lphilips at verity dot com>. It is described in ["Practical Algorithms for Programmers", Binstock & Rex, Addison Wesley, 1995].

参数

str: The input string.
phonemes: This parameter restricts the returned metaphone key to phonemes characters in length. The default value of 0 means no restriction.

返回值

Returns the metaphone key as a string, 或者在失败时返回 FALSE.

范例

Example #1 metaphone() basic example


<?php
var_dump(metaphone('programming'));
var_dump(metaphone('programmer'));
?>

以上例程的输出类似于：

string(7) "PRKRMNK"
string(6) "PRKRMR"

Example #2 Using the phonemes parameter


<?php
var_dump(metaphone('programming', 5));
var_dump(metaphone('programmer', 5));
?>

以上例程的输出类似于：

string(5) "PRKRM"
string(5) "PRKRM"

PHP手册 - N: Calculate the metaphone key of a string

用户评论:

Vipindas K.S (09-May-2008 05:49)

metaphone ======================= The metaphone() function can be used for spelling applications.This function returns the metaphone key of the string on success, or FALSE on failure.Its main use is when you are searching a genealogy database. check to see if a metaphone search is offered. It is also useful in making/searching family tree. Given below is a simple code that calculates and compares two strings to find whether its metaphone codes are equivalent. html code ========== <html> <body> <form action="test.php" name="test" method="get"> Name1:<input type="text" name="name1" /><br /> Name2:<input type="text" name="name2" /><br /> <input type="submit" name="submit" value="compare" /> </form>  <?php if(isset($_GET['submit'])) { $str1 = $_GET['name1']; $str2 = $_GET['name2']; $meta_one=metaphone($str1); $meta_two=metaphone($str2); echo "metaphone code for ".$str1." is ". $meta_one; echo "<br />"; echo "metaphone code for ".$str2." is ". $meta_two."<br>"; if($meta_one==$meta_two) { echo "metaphone codes are matching"; } else { echo "metaphone codes are not matching"; } } ?> </body> </html> Metaphone algorithm was developed by Lawrence Philips. Lawrence Philips' RULES follow: The 16 consonant sounds: |--- ZERO represents "th" | B X S K J T F H L M N P R 0 W Y Exceptions: Beginning of word: "ae-", "gn", "kn-", "pn-", "wr-" ----> drop first letter "Aebersold", "Gnagy", "Knuth", "Pniewski", "Wright" Beginning of word: "x" ----> change to "s" as in "Deng Xiaopeng" Beginning of word: "wh-" ----> change to "w" as in "Whalen" Transformations: B ----> B unless at the end of word after "m", as in "dumb", "McComb" C ----> X (sh) if "-cia-" or "-ch-" S if "-ci-", "-ce-", or "-cy-" SILENT if "-sci-", "-sce-", or "-scy-" K otherwise, including in "-sch-" D ----> J if in "-dge-", "-dgy-", or "-dgi-" T otherwise F ----> F G ----> SILENT if in "-gh-" and not at end or before a vowel in "-gn" or "-gned" in "-dge-" etc., as in above rule J if before "i", or "e", or "y" if not double "gg" K otherwise H ----> SILENT if after vowel and no vowel follows or after "-ch-", "-sh-", "-ph-", "-th-", "-gh-" H otherwise J ----> J K ----> SILENT if after "c" K otherwise L ----> L M ----> M N ----> N P ----> F if before "h" P otherwise Q ----> K R ----> R S ----> X (sh) if before "h" or in "-sio-" or "-sia-" S otherwise T ----> X (sh) if "-tia-" or "-tio-" 0 (th) if before "h" silent if in "-tch-" T otherwise V ----> F W ----> SILENT if not followed by a vowel W if followed by a vowel X ----> KS Y ----> SILENT if not followed by a vowel Y if followed by a vowel Z ----> S

php at casadebender dot com (27-Mar-2008 06:24)

A double metaphone pecl module is available: http://pecl.php.net/package/doublemetaphone

mail at spam-off dot iaindooley dot com (16-Jan-2004 08:37)

you can use the metaphone function quite effectively with phrases by taking the levenshtein distances between two metaphone codes, and then taking this as a percentage of the length of the original metaphone code. thus you can define a percentage error, (say 20%) and accept only matches that are closer than that. i've found this works quite effectively in a function i am using on my website where an album name that the user entered is verified against existing album names that may be similar. this is also an excellent way of people being able to vaguely remember a phrase and get several suggestions out of the database. so you could type "i stiched nine times" with an error percentage of, say, 50 and still get 'a stitch in time saves nine' back as a match.

server: zinkconsulting.com user: galen@ (26-Nov-2003 10:18)

A small warning about the double metaphone function/class implemented in php: it's slow. Very slow. On my Mac OS X box it takes roughly 4 seconds to calculate the double_metaphone of a given string 1,000 times and set a variable to that value. Given the exact same code, the built in metaphone function takes a mere 0.03 seconds. That's a huge difference. For reference, soundex takes about 0.015 seconds. I had dreams of ranking my person database search results with double_metaphone, but with searches yielding a few thousand results sometimes, this isn't terribly reasonable. I'm back to basic metaphone functions. I'd suggest anyone considering the use of the double_metaphone functionality weigh the slight improvement in results with the fact it's 100 times slower than the php function metaphone. I believe this difference is probably due mostly to implementation and optimization (php code vs. optimized internal php function). Anybody up for writing a double_metaphone function for php? Maybe php 5?