查找python列表之间的交集/差异

Question

我有两个python列表:

a = [('when', 3), ('why', 4), ('throw', 9), ('send', 15), ('you', 1)]

b = ['the', 'when', 'send', 'we', 'us']

我需要过滤掉与b中类似的所有元素.就像在这种情况下,我应该得到:

c = [('why', 4), ('throw', 9), ('you', 1)]

什么应该是最有效的方法？

Answer 1

列表理解将起作用.

a = [('when', 3), ('why', 4), ('throw', 9), ('send', 15), ('you', 1)]
b = ['the', 'when', 'send', 'we', 'us']
filtered = [i for i in a if not i[0] in b]

>>>print(filtered)
[('why', 4), ('throw', 9), ('you', 1)]

Answer 2

列表理解应该有效：

c = [item for item in a if item[0] not in b]

或者使用字典理解：

d = dict(a)
c = {key: value for key in d.iteritems() if key not in b}