得到3个列表之间的差异 [英] get difference between 3 lists

问题描述

我正在处理列表的差异.

I am working on differences of lists.

>>a = [1, 2, 3]
>>b = [2, 4, 5]
>>c = [3, 2, 6]

两组之间的对称性差异可以使用:

Symmetric difference between 2 sets can be done using:

>>z = set(a).symmetric_difference(set(b))
>>print z
>>set([1, 3, 4, 5])

如何获得3套之间的差异? 对于3套的差异，预期输出为:

How to get difference between 3 sets? For difference of 3 sets, expected output is :

expected output : set([1, 3, 4, 5, 6])

推荐答案

只需从并集中减去交集即可:

Just subtract the intersection from the union:

In [1]: a = set([1, 2, 3])

In [2]: b = set([2, 4, 5])

In [3]: c = set([3, 2, 6])

In [4]: (a | b | c) - (a & b & c)
Out[4]: set([1, 3, 4, 5, 6])

或者，归纳为任意集合集:

Or, to generalise to an arbitrary collection of sets:

In [10]: l = [a, b, c]

In [11]: reduce(set.union, l) - reduce(set.intersection, l)
Out[11]: set([1, 3, 4, 5, 6])

或:

In [13]: set.union(*l) - set.intersection(*l)
Out[13]: set([1, 3, 4, 5, 6])

(后者可能更可取.)

这篇关于得到3个列表之间的差异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！