Source code for similarityPy.measure.string_data.hamming_distance

# coding=utf-8
"""
Created on 18 January 2014
@author: Cenk Bircanoglu
"""
import operator

from similarityPy.measure.similarity_measure import SimilarityMeasure
from similarityPy.measure.similarity_measure_type import SimilarityMeasureType


[docs]class HammingDistance(SimilarityMeasure):
    similarity_measure_type = SimilarityMeasureType.DISTANCE_ABBR

    def _algorithm(self):
        if len(self._data) == 2:
            point_a = self._data[0]
            point_b = self._data[1]

            if len(point_a) == len(point_b):
                try:
                    point_a = point_a.lower()
                    point_b = point_b.lower()
                except:
                    pass
                equality_list = map(operator.eq, point_b, point_a)
                self._result = equality_list.count(False)

            else:
                raise ArithmeticError("You cant calculate Hamming distance of array has different sizes.")

        else:
            raise ArithmeticError("You must enter two array to find Hamming distance.")