如何比较两个列表中的项目Python 3.3 [英] How To Compare Items In Two Lists Python 3.3

问题描述

我尝试使用 cmp(list1，list2)来了解它在Python 3.3中不再受支持.我尝试了许多其他复杂的方法，但没有一个奏效.

I tried using cmp(list1, list2) to learn it's no longer supported in Python 3.3. I've tried many other complex approaches, but none have worked.

我有两个列表，每个列表都只包含单词，我希望它检查以查看两个单词中都有多少个单词，并返回其中的数字.

I have two lists of which both contain just words and I want it to check to see how many words feature in both and return the number for how many.

推荐答案

您可以使用& 像这样找到集合相交的长度:

You can find the length of the set intersection using & like this:

len(set(list1) & set(list2))

示例:

>>>len(set(['cat','dog','pup']) & set(['rat','cat','wolf']))
1
>>>set(['cat','dog','pup']) & set(['rat','cat','wolf'])
{'cat'}

或者，如果您由于某些原因不想使用集，则可以始终使用 collections.Counter ，它支持大多数多集操作:

Alternatively, if you don't want to use sets for some reason, you can always use collections.Counter, which supports most multiset operations:

>>> from collections import Counter 
>>> print(list((Counter(['cat','dog','wolf']) & Counter(['pig','fish','cat'])).elements()))
['cat']

这篇关于如何比较两个列表中的项目Python 3.3的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！