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Question

我正在研究 Apriori 算法，并试图通过使用用户定义的函数来解决它。该代码可在 Github 上获得 -：https ://gist.github.com/marcelcaraciolo/1423287

我无法获得这两行以及它们如何在循环中迭代。

            L1 = list(freq_sets[i])[:k - 2]
            L2 = list(freq_sets[j])[:k - 2]

包含这些行的实际函数：

def aprioriGen(freq_sets, k):
    "Generate the joint transactions from candidate sets"
    retList = []
    lenLk = len(freq_sets)
    for i in range(lenLk):
        for j in range(i + 1, lenLk):
            L1 = list(freq_sets[i])[:k - 2]
            L2 = list(freq_sets[j])[:k - 2]
            L1.sort()
            L2.sort()
            if L1 == L2:
                retList.append(freq_sets[i] | freq_sets[j])
    return retList

标签： pythonlist