# -*- coding: utf-8 -*-
# Copyright 2018 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.fingerprint._occurrence.
Cisłak & Grabowski's occurrence fingerprint
"""
from __future__ import (
absolute_import,
division,
print_function,
unicode_literals,
)
from ._fingerprint import MOST_COMMON_LETTERS_CG, _Fingerprint
__all__ = ['Occurrence', 'occurrence_fingerprint']
[docs]class Occurrence(_Fingerprint):
"""Occurrence Fingerprint.
Based on the occurrence fingerprint from :cite:`Cislak:2017`.
"""
[docs] def fingerprint(self, word, n_bits=16, most_common=MOST_COMMON_LETTERS_CG):
"""Return the occurrence fingerprint.
Parameters
----------
word : str
The word to fingerprint
n_bits : int
Number of bits in the fingerprint returned
most_common : list
The most common tokens in the target language, ordered by frequency
Returns
-------
int
The occurrence fingerprint
Examples
--------
>>> of = Occurrence()
>>> bin(of.fingerprint('hat'))
'0b110000100000000'
>>> bin(of.fingerprint('niall'))
'0b10110000100000'
>>> bin(of.fingerprint('colin'))
'0b1110000110000'
>>> bin(of.fingerprint('atcg'))
'0b110000000010000'
>>> bin(of.fingerprint('entreatment'))
'0b1110010010000100'
"""
word = set(word)
fingerprint = 0
for letter in most_common:
if letter in word:
fingerprint += 1
n_bits -= 1
if n_bits:
fingerprint <<= 1
else:
break
n_bits -= 1
if n_bits > 0:
fingerprint <<= n_bits
return fingerprint
[docs]def occurrence_fingerprint(
word, n_bits=16, most_common=MOST_COMMON_LETTERS_CG
):
"""Return the occurrence fingerprint.
This is a wrapper for :py:meth:`Occurrence.fingerprint`.
Parameters
----------
word : str
The word to fingerprint
n_bits : int
Number of bits in the fingerprint returned
most_common : list
The most common tokens in the target language, ordered by frequency
Returns
-------
int
The occurrence fingerprint
Examples
--------
>>> bin(occurrence_fingerprint('hat'))
'0b110000100000000'
>>> bin(occurrence_fingerprint('niall'))
'0b10110000100000'
>>> bin(occurrence_fingerprint('colin'))
'0b1110000110000'
>>> bin(occurrence_fingerprint('atcg'))
'0b110000000010000'
>>> bin(occurrence_fingerprint('entreatment'))
'0b1110010010000100'
"""
return Occurrence().fingerprint(word, n_bits, most_common)
if __name__ == '__main__':
import doctest
doctest.testmod()