Python – 元组列表交集（顺序无关）

给定元组列表，执行元素的元组交集，而不管它们的顺序。

Input : test_list1 = [(3, 4), (5, 6)], test_list2 = [(5, 4), (4, 3)] 
Output : {(3, 4)} 
Explanation : (3, 4) and (4, 3) are common, hence intersection ( order irrespective).

Input : test_list1 = [(3, 4), (5, 6)], test_list2 = [(5, 4), (4, 5)] 
Output : set() 
Explanation : No intersecting element present. 
 

方法#1：使用 sorted() + set() + & 运算符 + 列表推导
上述功能的组合可以用来解决这个问题。在此，我们对元组进行排序，并使用 &运算符进行交集。

Python3

# Python3 code to demonstrate working of
# Tuple List intersection [ Order irrespective ]
# Using sorted() + set() + & operator + list comprehension
 
# initializing lists
test_list1 = [(3, 4), (5, 6), (9, 10), (4, 5)]
test_list2 = [(5, 4), (3, 4), (6, 5), (9, 11)]
 
# printing original list
print("The original list 1 is : " + str(test_list1))
print("The original list 2 is : " + str(test_list2))
 
# Using sorted() + set() + & operator + list comprehension
# Using & operator to intersect, sorting before performing intersection
res = set([tuple(sorted(ele)) for ele in test_list1]) & set([tuple(sorted(ele)) for ele in test_list2])
 
# printing result
print("List after intersection : " + str(res))

输出 ：

The original list 1 is : [(3, 4), (5, 6), (9, 10), (4, 5)]
The original list 2 is : [(5, 4), (3, 4), (6, 5), (9, 11)]
List after intersection : {(4, 5), (3, 4), (5, 6)}

方法 #2：使用列表理解 + map() + freezeset() + &运算符
上述功能的组合可用于执行此任务。在此，我们执行将内部容器转换为集合、对其进行排序并执行交集的任务。 Frozenset 被用作它的 hashable，map() 需要 hashable 数据类型作为参数。

Python3

# Python3 code to demonstrate working of
# Tuple List intersection [ Order irrespective ]
# Using list comprehension + map() + frozenset() + & operator
 
# initializing lists
test_list1 = [(3, 4), (5, 6), (9, 10), (4, 5)]
test_list2 = [(5, 4), (3, 4), (6, 5), (9, 11)]
 
# printing original list
print("The original list 1 is : " + str(test_list1))
print("The original list 2 is : " + str(test_list2))
 
# Using list comprehension + map() + frozenset() + & operator
# frozenset used as map() requires hashable container, which
# set is not, result in frozenset format
res = set(map(frozenset, test_list1)) & set(map(frozenset, test_list2))
 
# printing result
print("List after intersection : " + str(res))

输出 ：

The original list 1 is : [(3, 4), (5, 6), (9, 10), (4, 5)]
The original list 2 is : [(5, 4), (3, 4), (6, 5), (9, 11)]
List after intersection : {frozenset({4, 5}), frozenset({5, 6}), frozenset({3, 4})}