# Copyright 2014-2020 by Christopher C. Little.
# This file is part of Abydos.
#
# Abydos is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Abydos is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Abydos. If not, see <http://www.gnu.org/licenses/>.
"""abydos.phonetic._fuzzy_soundex.
Fuzzy Soundex
"""
from unicodedata import normalize as unicode_normalize
from deprecation import deprecated
from ._phonetic import _Phonetic
from .. import __version__
__all__ = ['FuzzySoundex', 'fuzzy_soundex']
[docs]class FuzzySoundex(_Phonetic):
"""Fuzzy Soundex.
Fuzzy Soundex is an algorithm derived from Soundex, defined in
:cite:`Holmes:2002`.
.. versionadded:: 0.3.6
"""
_trans = dict(
zip(
(ord(_) for _ in 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'),
'0193017-07745501769301-7-9',
)
)
_alphabetic = dict(zip((ord(_) for _ in '01345679'), 'APTLNRKS'))
def __init__(self, max_length=5, zero_pad=True):
"""Initialize FuzzySoundex instance.
Parameters
----------
max_length : int
The length of the code returned (defaults to 4)
zero_pad : bool
Pad the end of the return value with 0s to achieve a max_length
string
.. versionadded:: 0.4.0
"""
# Clamp max_length to [4, 64]
if max_length != -1:
self._max_length = min(max(4, max_length), 64)
else:
self._max_length = 64
self._zero_pad = zero_pad
[docs] def encode_alpha(self, word):
"""Return the alphabetic Fuzzy Soundex code for a word.
Parameters
----------
word : str
The word to transform
Returns
-------
str
The alphabetic Fuzzy Soundex value
Examples
--------
>>> pe = FuzzySoundex()
>>> pe.encode_alpha('Christopher')
'KRSTP'
>>> pe.encode_alpha('Niall')
'NL'
>>> pe.encode_alpha('Smith')
'SNT'
>>> pe.encode_alpha('Schmidt')
'SNT'
.. versionadded:: 0.4.0
"""
code = self.encode(word).rstrip('0')
return code[:1] + code[1:].translate(self._alphabetic)
[docs] def encode(self, word):
"""Return the Fuzzy Soundex code for a word.
Parameters
----------
word : str
The word to transform
Returns
-------
str
The Fuzzy Soundex value
Examples
--------
>>> pe = FuzzySoundex()
>>> pe.encode('Christopher')
'K6931'
>>> pe.encode('Niall')
'N4000'
>>> pe.encode('Smith')
'S5300'
>>> pe.encode('Smith')
'S5300'
.. versionadded:: 0.1.0
.. versionchanged:: 0.3.6
Encapsulated in class
"""
word = unicode_normalize('NFKD', word.upper())
if not word:
if self._zero_pad:
return '0' * self._max_length
return '0'
if word[:2] in {'CS', 'CZ', 'TS', 'TZ'}:
word = 'SS' + word[2:]
elif word[:2] == 'GN':
word = 'NN' + word[2:]
elif word[:2] in {'HR', 'WR'}:
word = 'RR' + word[2:]
elif word[:2] == 'HW':
word = 'WW' + word[2:]
elif word[:2] in {'KN', 'NG'}:
word = 'NN' + word[2:]
if word[-2:] == 'CH':
word = word[:-2] + 'KK'
elif word[-2:] == 'NT':
word = word[:-2] + 'TT'
elif word[-2:] == 'RT':
word = word[:-2] + 'RR'
elif word[-3:] == 'RDT':
word = word[:-3] + 'RR'
word = word.replace('CA', 'KA')
word = word.replace('CC', 'KK')
word = word.replace('CK', 'KK')
word = word.replace('CE', 'SE')
word = word.replace('CHL', 'KL')
word = word.replace('CL', 'KL')
word = word.replace('CHR', 'KR')
word = word.replace('CR', 'KR')
word = word.replace('CI', 'SI')
word = word.replace('CO', 'KO')
word = word.replace('CU', 'KU')
word = word.replace('CY', 'SY')
word = word.replace('DG', 'GG')
word = word.replace('GH', 'HH')
word = word.replace('MAC', 'MK')
word = word.replace('MC', 'MK')
word = word.replace('NST', 'NSS')
word = word.replace('PF', 'FF')
word = word.replace('PH', 'FF')
word = word.replace('SCH', 'SSS')
word = word.replace('TIO', 'SIO')
word = word.replace('TIA', 'SIO')
word = word.replace('TCH', 'CHH')
sdx = word.translate(self._trans)
sdx = sdx.replace('-', '')
# remove repeating characters
sdx = self._delete_consecutive_repeats(sdx)
if word[0] in {'H', 'W', 'Y'}:
sdx = word[0] + sdx
else:
sdx = word[0] + sdx[1:]
sdx = sdx.replace('0', '')
if self._zero_pad:
sdx += '0' * self._max_length
return sdx[: self._max_length]
[docs]@deprecated(
deprecated_in='0.4.0',
removed_in='0.6.0',
current_version=__version__,
details='Use the FuzzySoundex.encode method instead.',
)
def fuzzy_soundex(word, max_length=5, zero_pad=True):
"""Return the Fuzzy Soundex code for a word.
This is a wrapper for :py:meth:`FuzzySoundex.encode`.
Parameters
----------
word : str
The word to transform
max_length : int
The length of the code returned (defaults to 4)
zero_pad : bool
Pad the end of the return value with 0s to achieve a max_length string
Returns
-------
str
The Fuzzy Soundex value
Examples
--------
>>> fuzzy_soundex('Christopher')
'K6931'
>>> fuzzy_soundex('Niall')
'N4000'
>>> fuzzy_soundex('Smith')
'S5300'
>>> fuzzy_soundex('Smith')
'S5300'
.. versionadded:: 0.1.0
"""
return FuzzySoundex(max_length, zero_pad).encode(word)
if __name__ == '__main__':
import doctest
doctest.testmod()