舉例說明python3 set方法功能

add（增加元素）

name = set(['Tom','Lucy','Ben'])name.add('Juny')print(name)#輸出：{'Lucy', 'Juny', 'Ben', 'Tom'}

clear（清空所有元素）

name = set(['Tom','Lucy','Ben'])name.clear()print(name)#輸出：set()

copy(拷貝set集合)

name = set(['Tom','Lucy','Ben'])new_name = name.copy()print(new_name)#輸出：{'Tom', 'Lucy', 'Ben'}

difference(返回兩個或多個集合中不同的元素，並產生新的集合)

A = set([2,3,4,5= set([3,4= set([2=

difference_update（刪除A集合裡面，在B集合中存在的元素。）

A = set([2,3,4,5])B = set([4,5])A.difference_update(B)print(A)#輸出：{2, 3}

discard(移除元素)

n = set([2,3,4])n.discard(3)print(n)#輸出：{2, 4}

intersection(取交集，並產生新的集合)

n1 = set([2,3,4,5])n2 = set([4,5,6,7])n = n1.intersection(n2)print(n)#輸出：{4, 5}

intersection_update(取交集，修改原來的集合)

n1 = set([2,3,4,5])n2 = set([4,5,6,7])n1.intersection_update(n2)print(n1)#輸出：{4, 5}

isdisjoint(判斷交集，是返回False，否返回True)

n1 = set([2,3,4,5])n2 = set([4,5,6,7])print(n1.isdisjoint(n2))#輸出：False

issubset(判斷子集)

A = set([2,3])B = set([2,3,4,5])print(A.issubset(B))#輸出：True#A是B的子集

issuperset(判斷父集)

A = set([2,3])B = set([2,3,4,5])print(B.issuperset(A))# 輸出：True#B是A的父集

pop(隨機移除一個元素)

n = set([2,3,4,5])n1 = n.pop()print(n,n1)# 輸出：{3, 4, 5} 2

remove(移除指定元素)

n = set([2,3,4,5])n.remove(2)print(n)# 輸出：{3, 4, 5}

symmetric_difference(取交集，並產生新的集合)

A = set([2,3,4,5])B = set([4,5,6,7])print(A.symmetric_difference(B))# 輸出：{2, 3, 6, 7}

symmetric_difference_update(取交集，改變原來的集合)

A = set([2,3,4,5])B = set([4,5,6,7])A.symmetric_difference_update(B)print(A)# 輸出：{2, 3, 6, 7}

union（取並集，並產生新的集合）

A = set([2,3,4,5])B = set([4,5,6,7])print(A.union(B))# 輸出：{2, 3, 4, 5, 6, 7}

update(取並集，改變原來的集合)

A = set([2,3,4,5])B = set([4,5,6,7])A.update(B)print(A)# 輸出：{2, 3, 4, 5, 6, 7}