python - 计算 Python 列表列表中元素的频率

Question

比如说，我有以下排序列表:

列表 1:(12,24,36)

list 2:(3,5,12,24)

list 3:(36,41,69)

我想找出每个元素在整个列表列表中出现的频率。我在 python 中想出了一个丑陋的模块，但我想知道是否有一些库函数..

编辑:请在下面找到代码

def find_frequency(transactions,list):
    freq = 0
    for items_transaction in transactions:
        flag = 0
        for candidate in list:
            if candidate not in items_transaction:
                flag = 1
                break
        if flag == 0:
            freq += 1
    return freq

Answer 1

Counter 会做我认为您正在寻找的事情:

>>> from itertools import chain
>>> from collections import Counter
>>> list1, list2, list3 = [12,24,36], [3,5,12,24], [36,41,69]
>>> Counter(chain(list1, list2, list3))
Counter({3: 1, 5: 1, 12: 2, 24: 2, 36: 2, 41: 1, 69: 1})