abydos.distance._goodman_kruskal_tau_a.GoodmanKruskalTauA.sim() - Code Metrics - Inspection of "0.4.1" - chrislit/abydos - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Pull Request — master (#225)

by Chris

created 2019-07-12 00:08 UTC

GoodmanKruskalTauA.sim() A

↳ Parent: abydos.distance._goodman_kruskal_tau_a

Complexity

Conditions

Size

Total Lines	51
Code Lines	16

Duplication

Lines	51
Ratio	100 %

Code Coverage

Tests	15
CRAP Score	5

Importance

Changes

Metric	Value
eloc	16
dl	51
loc	51
ccs	15
cts	15
cp	1
rs	9.1333
c	0
b	0
f	0
cc	5
nop	3
crap	5

How to fix Long Method

# -*- coding: utf-8 -*-

# Copyright 2019 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.distance._goodman_kruskal_tau_a.

Goodman & Kruskal's Tau A similarity
"""

from __future__ import (
    absolute_import,
    division,
    print_function,
    unicode_literals,
)

from ._token_distance import _TokenDistance

__all__ = ['GoodmanKruskalTauA']


class GoodmanKruskalTauA(_TokenDistance):

    r"""Goodman & Kruskal's Tau A similarity.

    For two sets X and Y and a population N, Goodman & Kruskal's :math:`\tau_a`
    similarity :cite:`Goodman:1954`, by analogy with :math:`\tau_b`, is

        .. math::

            sim_{GK_{\tau_a}}(X, Y) =
            \frac{\frac{\frac{|X \cap Y|}{|N|}^2 +
            \frac{|Y \setminus X|}{|N|}^2}{\frac{|Y|}{|N|}}+
            \frac{\frac{|X \setminus Y|}{|N|}^2 +
            \frac{|(N \setminus X) \setminus Y|}{|N|}^2}
            {\frac{|N \setminus X|}{|N|}} -
            (\frac{|X|}{|N|}^2 + \frac{|N \setminus X|}{|N|}^2)}
            {1 - (\frac{|X|}{|N|}^2 + \frac{|N \setminus X|}{|N|}^2)}

    In :ref:`2x2 confusion table terms <confusion_table>`, where a+b+c+d=n,
    after each term has been converted to a proportion by dividing by n, this
    is

        .. math::

            sim_{GK_{\tau_a}} =
            \frac{
            \frac{a^2 + c^2}{a+c} +
            \frac{b^2 + d^2}{b+d} -
            ((a+b)^2 + (c+d)^2)}
            {1 - ((a+b)^2 + (c+d)^2)}

    .. versionadded:: 0.4.0
    """

    def __init__(
        self,
        alphabet=None,
        tokenizer=None,
        intersection_type='crisp',
        normalizer='proportional',
        **kwargs
    ):
        """Initialize GoodmanKruskalTauA instance.

        Parameters
        ----------
        alphabet : Counter, collection, int, or None
            This represents the alphabet of possible tokens.
            See :ref:`alphabet <alphabet>` description in
            :py:class:`_TokenDistance` for details.
        tokenizer : _Tokenizer
            A tokenizer instance from the :py:mod:`abydos.tokenizer` package
        intersection_type : str
            Specifies the intersection type, and set type as a result:
            See :ref:`intersection_type <intersection_type>` description in
            :py:class:`_TokenDistance` for details.
        normalizer : str
            Specifies the normalization type. See :ref:`normalizer <alphabet>`
            description in :py:class:`_TokenDistance` for details.
        **kwargs
            Arbitrary keyword arguments

        Other Parameters
        ----------------
        qval : int
            The length of each q-gram. Using this parameter and tokenizer=None
            will cause the instance to use the QGram tokenizer with this
            q value.
        metric : _Distance
            A string distance measure class for use in the ``soft`` and
            ``fuzzy`` variants.
        threshold : float
            A threshold value, similarities above which are counted as
            members of the intersection for the ``fuzzy`` variant.


        .. versionadded:: 0.4.0

        """
        super(GoodmanKruskalTauA, self).__init__(
            alphabet=alphabet,
            tokenizer=tokenizer,
            intersection_type=intersection_type,
            normalizer=normalizer,
            **kwargs
        )

    def sim(self, src, tar):
        """Return Goodman & Kruskal's Tau A similarity of two strings.

        Parameters
        ----------
        src : str
            Source string (or QGrams/Counter objects) for comparison
        tar : str
            Target string (or QGrams/Counter objects) for comparison

        Returns
        -------
        float
            Goodman & Kruskal's Tau A similarity

        Examples
        --------
        >>> cmp = GoodmanKruskalTauA()
        >>> cmp.sim('cat', 'hat')
        0.3304969657208484
        >>> cmp.sim('Niall', 'Neil')
        0.22137604585914503
        >>> cmp.sim('aluminum', 'Catalan')
        0.05991264724130685
        >>> cmp.sim('ATCG', 'TAGC')
        4.119695274745721e-05


        .. versionadded:: 0.4.0

        """
        self._tokenize(src, tar)

        a = self._intersection_card()
        b = self._src_only_card()
        c = self._tar_only_card()
        d = self._total_complement_card()

        if a + b == 0 or a + c == 0:
            return 0.0

        fp = (a * a + c * c) / (a + c)

        sp = b * b + d * d
        if sp:
            sp /= b + d

        num = fp + sp - (a + b) ** 2 - (c + d) ** 2
        if num > 1e-14:
            return num / (1 - (a + b) ** 2 - (c + d) ** 2)
        return 0.0  # pragma: no cover


if __name__ == '__main__':
    import doctest

    doctest.testmod()


1			# -- coding: utf-8 --
2
3			# Copyright 2019 by Christopher C. Little.
4			# This file is part of Abydos.
5			#
6			# Abydos is free software: you can redistribute it and/or modify
7			# it under the terms of the GNU General Public License as published by
8			# the Free Software Foundation, either version 3 of the License, or
9			# (at your option) any later version.
10			#
11			# Abydos is distributed in the hope that it will be useful,
12			# but WITHOUT ANY WARRANTY; without even the implied warranty of
13			# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			# GNU General Public License for more details.
15			#
16			# You should have received a copy of the GNU General Public License
17			# along with Abydos. If not, see <http://www.gnu.org/licenses/>.
18
19	1		"""abydos.distance._goodman_kruskal_tau_a.
20
21			Goodman & Kruskal's Tau A similarity
22			"""
23
24	1		from __future__ import (
25			absolute_import,
26			division,
27			print_function,
28			unicode_literals,
29			)
30
31	1		from ._token_distance import _TokenDistance
32
33	1		__all__ = ['GoodmanKruskalTauA']
34
35
36	1	View Code Duplication	class GoodmanKruskalTauA(_TokenDistance):
			0 ignored issues – show Duplication introduced 2019-02-15 07:24 UTC by Report Bug Copy Issue Report This code seems to be duplicated in your project. Loading history...
37			r"""Goodman & Kruskal's Tau A similarity.
38
39			For two sets X and Y and a population N, Goodman & Kruskal's :math:`\tau_a`
40			similarity :cite:`Goodman:1954`, by analogy with :math:`\tau_b`, is
41
42			.. math::
43
44			sim_{GK_{\tau_a}}(X, Y) =
45			\frac{\frac{\frac{\|X \cap Y\|}{\|N\|}^2 +
46			\frac{\|Y \setminus X\|}{\|N\|}^2}{\frac{\|Y\|}{\|N\|}}+
47			\frac{\frac{\|X \setminus Y\|}{\|N\|}^2 +
48			\frac{\|(N \setminus X) \setminus Y\|}{\|N\|}^2}
49			{\frac{\|N \setminus X\|}{\|N\|}} -
50			(\frac{\|X\|}{\|N\|}^2 + \frac{\|N \setminus X\|}{\|N\|}^2)}
51			{1 - (\frac{\|X\|}{\|N\|}^2 + \frac{\|N \setminus X\|}{\|N\|}^2)}
52
53			In :ref:`2x2 confusion table terms <confusion_table>`, where a+b+c+d=n,
54			after each term has been converted to a proportion by dividing by n, this
55			is
56
57			.. math::
58
59			sim_{GK_{\tau_a}} =
60			\frac{
61			\frac{a^2 + c^2}{a+c} +
62			\frac{b^2 + d^2}{b+d} -
63			((a+b)^2 + (c+d)^2)}
64			{1 - ((a+b)^2 + (c+d)^2)}
65
66			.. versionadded:: 0.4.0
67			"""
68
69	1		def __init__(
70			self,
71			alphabet=None,
72			tokenizer=None,
73			intersection_type='crisp',
74			normalizer='proportional',
75			**kwargs
76			):
77			"""Initialize GoodmanKruskalTauA instance.
78
79			Parameters
80			----------
81			alphabet : Counter, collection, int, or None
82			This represents the alphabet of possible tokens.
83			See :ref:`alphabet <alphabet>` description in
84			:py:class:`_TokenDistance` for details.
85			tokenizer : _Tokenizer
86			A tokenizer instance from the :py:mod:`abydos.tokenizer` package
87			intersection_type : str
88			Specifies the intersection type, and set type as a result:
89			See :ref:`intersection_type <intersection_type>` description in
90			:py:class:`_TokenDistance` for details.
91			normalizer : str
92			Specifies the normalization type. See :ref:`normalizer <alphabet>`
93			description in :py:class:`_TokenDistance` for details.
94			**kwargs
95			Arbitrary keyword arguments
96
97			Other Parameters
98			----------------
99			qval : int
100			The length of each q-gram. Using this parameter and tokenizer=None
101			will cause the instance to use the QGram tokenizer with this
102			q value.
103			metric : _Distance
104			A string distance measure class for use in the ``soft`` and
105			``fuzzy`` variants.
106			threshold : float
107			A threshold value, similarities above which are counted as
108			members of the intersection for the ``fuzzy`` variant.
109
110
111			.. versionadded:: 0.4.0
112
113			"""
114	1		super(GoodmanKruskalTauA, self).__init__(
115			alphabet=alphabet,
116			tokenizer=tokenizer,
117			intersection_type=intersection_type,
118			normalizer=normalizer,
119			**kwargs
120			)
121
122	1		def sim(self, src, tar):
123			"""Return Goodman & Kruskal's Tau A similarity of two strings.
124
125			Parameters
126			----------
127			src : str
128			Source string (or QGrams/Counter objects) for comparison
129			tar : str
130			Target string (or QGrams/Counter objects) for comparison
131
132			Returns
133			-------
134			float
135			Goodman & Kruskal's Tau A similarity
136
137			Examples
138			--------
139			>>> cmp = GoodmanKruskalTauA()
140			>>> cmp.sim('cat', 'hat')
141			0.3304969657208484
142			>>> cmp.sim('Niall', 'Neil')
143			0.22137604585914503
144			>>> cmp.sim('aluminum', 'Catalan')
145			0.05991264724130685
146			>>> cmp.sim('ATCG', 'TAGC')
147			4.119695274745721e-05
148
149
150			.. versionadded:: 0.4.0
151
152			"""
153	1		self._tokenize(src, tar)
154
155	1		a = self._intersection_card()
156	1		b = self._src_only_card()
157	1		c = self._tar_only_card()
158	1		d = self._total_complement_card()
159
160	1		if a + b == 0 or a + c == 0:
161	1		return 0.0
162
163	1		fp = (a * a + c * c) / (a + c)
164
165	1		sp = b * b + d * d
166	1		if sp:
167	1		sp /= b + d
168
169	1		num = fp + sp - (a + b) 2 - (c + d) 2
170	1		if num > 1e-14:
171	1		return num / (1 - (a + b) 2 - (c + d) 2)
172			return 0.0 # pragma: no cover
173
174
175			if __name__ == '__main__':
176			import doctest
177
178			doctest.testmod()
179

chrislit / abydos

Pull Request — master (#225)

GoodmanKruskalTauA.sim() A

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How to fix Long Method

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