标签:add set ror 方法 数据类型 color union pop python
1. 注意列表和集合的区别 set
列表表现形式: list_1 = [1,3,4]; 集合表现形式:set_1= set()
list_1 = [1,2,3,4,23,4,2] print(list_1,type(list_1)) list_1 = set(list_1) print(list_1,type(list_1)) list_2 = set([2,4,6,8,10]) print(list_2,type(list_2)) #运行结果 [1, 2, 3, 4, 23, 4, 2] <class ‘list‘> {1, 2, 3, 4, 23} <class ‘set‘> {8, 2, 10, 4, 6} <class ‘set‘>
2. 集合的关系:
############################# 集合的关系测试 part ################################### #交集 print(list_1.intersection(list_2)) #对称差集 除去两个集合的交集的那部分 print(list_1.symmetric_difference(list_2)) #并集 print(list_1.union(list_2)) #差集 # is in list_1 , but not in list_2 print(list_1.difference(list_2)) # is in list_2, but not in list_1 print(list_2.difference(list_1)) #子集 list_3 = set([6,8,10]) print(list_3.issubset(list_2)) #父集 print(list_2.issuperset(list_3)) #""" Return True if two sets have a null intersection. """ print(list_1.isdisjoint(list_3)) print(list_1.isdisjoint(list_2)) ‘‘‘
"& | - ^ " 集合关系的另一种表示方法
#交集 print("交集->", list_1 & list_2) #union print("并集->", list_1 | list_2) # difference print("difference-->",list_1 - list_2) # is in list_1 but not in list_2 #对称差集 print("对称差集-->", list_1 ^ list_2)
3. 集合的方法 add , update , remove, len, in , not in , pop, discard
list_1 = (1,3,5,7) list_2 = ([1,3,5,7]) list_3 = set([1,3,5,7]) print(list_1,type(list_1)) print(list_2,type(list_2)) print(list_3,type(list_3)) #1.添加一项 add, 添加多项update list_3.add(9) print("test1--",list_3) list_3.update([11,13]) print("test2--",list_3) # 2.移走一项 list_3.remove(11) print("test3--",list_3) #.3 长度 print("test4--",len(list_3)) # 4.在不在里面 print("test5---", 6 in list_3, 3 in list_3, 11 not in list_3) # 5.删除任意的set element ,并返回 print(list_3.pop()) list_3.discard() # Remove an element from a set if it is a member.If the element is not a member, do nothing. list_3.remove() #Remove an element from a set; it must be a member. If the element is not a member, raise a KeyError
标签:add set ror 方法 数据类型 color union pop python
原文地址:http://www.cnblogs.com/frankb/p/6204666.html