|
:''Lawrence Philips redirects here. For the football player, see Lawrence Phillips. Metaphone is a phonetic algorithm, published by Lawrence Philips in 1990, for indexing words by their English pronunciation.〔Hanging on the Metaphone, Lawrence Philips. Computer Language, Vol. 7, No. 12 (December), 1990.〕 It fundamentally improves on the Soundex algorithm by using information about variations and inconsistencies in English spelling and pronunciation to produce a more accurate encoding, which does a better job of matching words and names which sound similar. As with Soundex, similar sounding words should share the same keys. Metaphone is available as a built-in operator in a number of systems. The original author later produced a new version of the algorithm, which he named Double Metaphone. Contrary to the original algorithm whose application is limited to English only, this version takes into account spelling peculiarities of a number of other languages. In 2009 Lawrence Philips released a third version, called Metaphone 3, which achieves an accuracy of approximately 99% for English words, non-English words familiar to Americans, and first names and family names commonly found in the United States, having been developed according to modern engineering standards against a test harness of prepared correct encodings. ==Procedure== Original Metaphone codes use the 16 consonant symbols 0BFHJKLMNPRSTWXY.〔http://www.sound-ex.com/alternative_zu_soundex〕 The '0' represents "th" (as an ASCII approximation of Θ), 'X' represents "sh" or "ch", and the others represent their usual English pronunciations. The vowels AEIOU are also used, but only at the beginning of the code.〔http://www.morfoedro.it/doc.php?n=222&lang=en〕 This table summarizes most of the rules in the original implementation: # Drop duplicate adjacent letters, except for C. # If the word begins with 'KN', 'GN', 'PN', 'AE', 'WR', drop the first letter. # Drop 'B' if after 'M' at the end of the word. # 'C' transforms to 'X' if followed by 'IA' or 'H' (unless in latter case, it is part of '-SCH-', in which case it transforms to 'K'). 'C' transforms to 'S' if followed by 'I', 'E', or 'Y'. Otherwise, 'C' transforms to 'K'. # 'D' transforms to 'J' if followed by 'GE', 'GY', or 'GI'. Otherwise, 'D' transforms to 'T'. # Drop 'G' if followed by 'H' and 'H' is not at the end or before a vowel. Drop 'G' if followed by 'N' or 'NED' and is at the end. # 'G' transforms to 'J' if before 'I', 'E', or 'Y', and it is not in 'GG'. Otherwise, 'G' transforms to 'K'. # Drop 'H' if after vowel and not before a vowel. # 'CK' transforms to 'K'. # 'PH' transforms to 'F'. # 'Q' transforms to 'K'. # 'S' transforms to 'X' if followed by 'H', 'IO', or 'IA'. # 'T' transforms to 'X' if followed by 'IA' or 'IO'. 'TH' transforms to '0'. Drop 'T' if followed by 'CH'. # 'V' transforms to 'F'. # 'WH' transforms to 'W' if at the beginning. Drop 'W' if not followed by a vowel. # 'X' transforms to 'S' if at the beginning. Otherwise, 'X' transforms to 'KS'. # Drop 'Y' if not followed by a vowel. # 'Z' transforms to 'S'. # Drop all vowels unless it is the beginning. It should be noted, however, that this table does not constitute a complete description of the original Metaphone algorithm, and the algorithm cannot be coded correctly from it. Original Metaphone contained many errors and was superseded by Double Metaphone, and in turn Double Metaphone and original Metaphone were superseded by Metaphone 3, which corrects thousands of miscodings that will be produced by the first two versions. To implement Metaphone without purchasing a (source code) copy of Metaphone 3, the best guide would be the reference implementation of Double Metaphone, which may be found (here ). == Double Metaphone == The Double Metaphone phonetic encoding algorithm is the second generation of this algorithm. Its implementation was described in the June 2000 issue of ''C/C++ Users Journal''. It makes a number of fundamental design improvements over the original Metaphone algorithm. It is called "Double" because it can return both a primary and a secondary code for a string; this accounts for some ambiguous cases as well as for multiple variants of surnames with common ancestry. For example, encoding the name "Smith" yields a primary code of ''SM0'' and a secondary code of ''XMT'', while the name "Schmidt" yields a primary code of ''XMT'' and a secondary code of ''SMT''—both have ''XMT'' in common. Double Metaphone tries to account for myriad irregularities in English of Slavic, Germanic, Celtic, Greek, French, Italian, Spanish, Chinese, and other origin. Thus it uses a much more complex ruleset for coding than its predecessor; for example, it tests for approximately 100 different contexts of the use of the letter C alone. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「:''Lawrence Philips redirects here. For the football player, see Lawrence Phillips.Metaphone is a phonetic algorithm, published by Lawrence Philips in 1990, for indexing words by their English pronunciation.Hanging on the Metaphone, Lawrence Philips. Computer Language, Vol. 7, No. 12 (December), 1990. It fundamentally improves on the Soundex algorithm by using information about variations and inconsistencies in English spelling and pronunciation to produce a more accurate encoding, which does a better job of matching words and names which sound similar. As with Soundex, similar sounding words should share the same keys. Metaphone is available as a built-in operator in a number of systems.The original author later produced a new version of the algorithm, which he named Double Metaphone. Contrary to the original algorithm whose application is limited to English only, this version takes into account spelling peculiarities of a number of other languages. In 2009 Lawrence Philips released a third version, called Metaphone 3, which achieves an accuracy of approximately 99% for English words, non-English words familiar to Americans, and first names and family names commonly found in the United States, having been developed according to modern engineering standards against a test harness of prepared correct encodings.==Procedure==Original Metaphone codes use the 16 consonant symbols 0BFHJKLMNPRSTWXY.http://www.sound-ex.com/alternative_zu_soundex The '0' represents "th" (as an ASCII approximation of Θ), 'X' represents "sh" or "ch", and the others represent their usual English pronunciations. The vowels AEIOU are also used, but only at the beginning of the code.http://www.morfoedro.it/doc.php?n=222&lang=en This table summarizes most of the rules in the original implementation:」の詳細全文を読む スポンサード リンク
|