from .shingle_based import ShingleBased from .string_distance import NormalizedStringDistance from .string_similarity import NormalizedStringSimilarity class OverlapCoefficient(ShingleBased, NormalizedStringDistance, NormalizedStringSimilarity): def __init__(self, k=3): super().__init__(k) def distance(self, s0, s1): return 1.0 - self.similarity(s0, s1) def similarity(self, s0, s1): if s0 is None: raise TypeError("Argument s0 is NoneType.") if s1 is None: raise TypeError("Argument s1 is NoneType.") if s0 == s1: return 1.0 union = set() profile0, profile1 = self.get_profile(s0), self.get_profile(s1) for k in profile0.keys(): union.add(k) for k in profile1.keys(): union.add(k) inter = int(len(profile0.keys()) + len(profile1.keys()) - len(union)) return inter / min(len(profile0), len(profile1))