python - 2 列表中的缺失值和附加值

Question

我有两个列表:

list1 = ['1','2','3','4','5','6']
list2 = ['4','5','6','7','8']

现在我想在 list2 中找到缺失值和附加值。

输出应该是:

Missing value = 1,2,3
Additional Value = 7,8

Answer 1

使用python sets列出差异:

set(list1).difference(list2)
set(list2).difference(list1)

结果:

>>> print 'Missing values =', ','.join(set(list1).difference(list2))
Missing values = 1,3,2
>>> print 'Additional values =', ','.join(set(list2).difference(list1))
Additional values = 7,8

如果顺序很重要，那么您仍然需要使用集合:

set1, set2 = set(list1), set(list2)
[i for i in list1 if i not in set2]
[i for i in list2 if i not in set1]

结果:

>>> print 'Missing values =', ','.join([i for i in list1 if i not in set2])
Missing values = 1,2,3
>>> print 'Missing values =', ','.join([i for i in list2 if i not in set1])
Additional values = 7,8