Calculates the metaphone key of string.
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].
The input string.
This parameter restricts the returned metaphone key to max_phonemes characters in length. However, the resulting phonemes are always transcribed completely, so the resulting string length may be slightly longer than max_phonemes. The default value of 0 means no restriction.
Returns the metaphone key as a string.
|8.0.0||The function returned false on failure.|