Source code for abydos.phonetic._refined_soundex

# Copyright 2014-2020 by Christopher C. Little.
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"""abydos.phonetic._refined_soundex.

Refined Soundex
"""

from unicodedata import normalize as unicode_normalize

from ._phonetic import _Phonetic

__all__ = ['RefinedSoundex']


[docs]class RefinedSoundex(_Phonetic): """Refined Soundex. This is Soundex, but with more character classes. It was defined at :cite:`Boyce:1998`. .. versionadded:: 0.3.6 """ _trans = dict( zip( (ord(_) for _ in 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'), '01360240043788015936020505', ) ) _alphabetic = dict(zip((ord(_) for _ in '123456789'), 'PFKGZTLNR')) def __init__( self, max_length: int = -1, zero_pad: bool = False, retain_vowels: bool = False, ) -> None: """Initialize RefinedSoundex instance. Parameters ---------- max_length : int The length of the code returned (defaults to unlimited) zero_pad : bool Pad the end of the return value with 0s to achieve a max_length string retain_vowels : bool Retain vowels (as 0) in the resulting code .. versionadded:: 0.4.0 """ self._max_length = max_length self._zero_pad = zero_pad self._retain_vowels = retain_vowels
[docs] def encode_alpha(self, word: str) -> str: """Return the alphabetic Refined Soundex code for a word. Parameters ---------- word : str The word to transform Returns ------- str The alphabetic Refined Soundex value Examples -------- >>> pe = RefinedSoundex() >>> pe.encode_alpha('Christopher') 'CRKTPR' >>> pe.encode_alpha('Niall') 'NL' >>> pe.encode_alpha('Smith') 'SNT' >>> pe.encode_alpha('Schmidt') 'SKNT' .. versionadded:: 0.4.0 """ code = self.encode(word).rstrip('0') return code[:1] + code[1:].translate(self._alphabetic)
[docs] def encode(self, word: str) -> str: """Return the Refined Soundex code for a word. Parameters ---------- word : str The word to transform Returns ------- str The Refined Soundex value Examples -------- >>> pe = RefinedSoundex() >>> pe.encode('Christopher') 'C93619' >>> pe.encode('Niall') 'N7' >>> pe.encode('Smith') 'S86' >>> pe.encode('Schmidt') 'S386' .. versionadded:: 0.3.0 .. versionchanged:: 0.3.6 Encapsulated in class """ # uppercase, normalize, decompose, and filter non-A-Z out word = unicode_normalize('NFKD', word.upper()) word = ''.join(c for c in word if c in self._uc_set) # apply the Soundex algorithm sdx = word[:1] + word[1:].translate(self._trans) sdx = self._delete_consecutive_repeats(sdx) if not self._retain_vowels: sdx = sdx.replace('0', '') # Delete vowels, H, W, Y if self._max_length > 0: if self._zero_pad: sdx += '0' * self._max_length sdx = sdx[: self._max_length] return sdx
if __name__ == '__main__': import doctest doctest.testmod()