一:集合相关操作与相关函数

1.集合相关操作(交叉并补)

(1)intersection() 交集

set1 = {"one","two","three"}

set2 = {"four","five","one"}

res = set1.intersection(set2)

print(res)

res = set1 & set2

print(res)

(2)difference() 差集

set1= {"one","two","three","four","five"}

set2 = {"six","seven","eigth","four"}

res = set1.difference(set2)

print(res)

res = set1 - set2   #s1 - s2 中有的元素，剩下的元素为结果

print(res)

(3)unoion() 并集

set1= {"one","two","three","four","five"}

set2 = {"six","seven","eigth","four"}

res = set1.union(set2)

print(res)

res = set1 | set2

print(res)

(4)symmrtric_difference() 对此差集(补集情况涵盖在其中)

set1= {"one","two","three","four","five"}

set2 = {"six","seven","eigth","four"}

res = set1.symmetric_difference(set2)

print(res)

res = set1 ^ set2

print(res)

(5)issubset()判断是否子集

set1 = {"one","two","three"}

set2 = {"one"}

res = set2.issubset(set1)  #可以完全一样

print(res)

#真子集: 2个集合不是完全一样的

res = set2 <= set1

print(res)

# res = set1.issuperset(set2)

# #也就是issubset()和issuperset()在两个集合元素相同的情况下都是Ture# print(res)

(6)issuperset() 判断是否是父集

set1 = {"one","two","three"}

set2 = {"one"}

res = set1.issuperset(set2)

print(res)

res = set1 >= set2 #>= 是要用等于的

print(res)

(7)isdisjoint()

检测两集合是否相交 不相交Ture相交False

set1 = {"one","two","three"}

set2 = {"one"}

res = set1.isdisjoint(set2)

print(res)

2.集合相关函数

(1)增 add() update()

#add()相集合中添加数据

print("==========增============")

setvar = {"one","two","three"}

setvar.add("four")

print(setvar)

print("==========update============")

#update()迭代着增加update (可迭代性数据)

setvar.update(["one","two"])

print(setvar)

print("==========删============")

(2)删除 clear() pop() discard()

#clear()清空集合

setvar = {"one","two","three"}

setvar.pop()

print(setvar)

#pop()随机删除集合的一个数据

setvar = {"one","two","three"}

setvar.remove("three")

#setvar.remove("three123") #error,删除原来没有的元素会出错

print(setvar)

#discard()删除集合中指定的值(不存在的不删除 推荐使用)

setvar = {"one","two","three"}

res = setvar.discard("three123")

print(setvar)

3.冰冻集合(只能做交差并补)

#frozenset可墙砖容器类型数据变为冰冻集合#冰冻集合一旦创建,不能再进行任何修改,只能做交差并补

#(1) 声明空的冰冻集合

fz = frozenset()

print(fz,type(fz))

fz = frozenset([1,2,3,4])

print(fz,type(fz))

#fz2 =frozenset("2345")  #注意字符串类型

fz2 = frozenset((2,3,4,5))

print(fz2,type(fz2))

fz2 = fz | fz2  #并集

print(fz2,type(fz2))

#fz1.add("456") #error 不允许添加或者删除操作

二.字典相关的函数

1.字典的相关函数(增删改查)

# (1)增

dictvar = {}

dictvar['top'] ="剑圣"

dictvar['moddle'] = "妲己"

dictvar['bottom'] = "鲁班七号"

dictvar['jungle'] = "刘备"

dictvar['support'] = "刘邦"

dictvar['top'] ="凯"

#如果键和前面的元素相同的情况下,将相同键的对应的值进行更新

print(dictvar)

#fromkeys()使用一组键和默认值创建字典

listvar = ["a","b"]

dict = {}.fromkeys(listvar,None)

print(dict)

#不推荐使用fromkeys

'''

dict = {}.fromkeys(listvar,[])

dic['a'].append(55)

print(dict('b'))

'''

#(2)删除

#pop()通过键去删除键值对(若没有该键可设置默认值,预防报错)

dictvar = {'top': '凯', 'middle': '妲己', 'bottom': '鲁班七号', 'jungle': '刘备', 'support': '刘邦'}

dictvar.pop('middle')

print(dictvar)

#dictvar.pop("modegdiqg")

dictvar.pop("dgqidq","该键不存在")

print(dictvar)

#popitem()删除最后一个键值对3.6版本

dictvar = {'top': '凯', 'middle': '妲己', 'bottom': '鲁班七号', 'jungle': '刘备', 'support': '刘邦'}

dictvar.popitem()

print(dictvar)

#clear()清空字典

dictvar.clear()

print(dictvar)

#(3)改

#update()批量更新(有该键就更新,没有该键就添加)

dict = { 'jungle': '刘备', 'support': '刘邦'}

#dict.update{{'top':"关羽",'middle':"武则天"}}

#写法一(推荐)

dict.update({'top':"花木兰",'middle':"武则天","support":"蔡文姬"})

print(dict)

#写法二:

dict.update(abc="23",bbb="3ew",ccc="4567")

print(dict)

#(4)查

#get()通过键获取值(若没有该键可设置默认值,预防报错)

dictvar = {'top': '凯', 'middle': '妲己', 'bottom': '鲁班七号', 'jungle': '刘备', 'support': '刘邦'}

#dictvar['top123'] error

res = dictvar.get("top123")

#如果没有该键,默认返回None,如果指定默认值,则返回默认值

res = dictvar.get("top123","对不起,没有该键")

print(res)

2.字典的方法 keys() values() items()

#keys()将字典的键组成新的迭代对象

dictvar = {'top': '凯', 'middle': '妲己', 'bottom': '鲁班七号', 'jungle': '刘备', 'support': '刘邦'}

for i in dictvar:

print(i)

#能够遍历就证明具有可迭代性

res = dictvar.keys()

print(res)

for i in res:

print(i)

#values()将字典中的值组成新的可迭代对象

res = dictvar.values()

print(res)

for i in res:

print(i)

#items()将字典的键值对凑成一个个元组,组成新的可迭代对象

res = dictvar.items()

print(res)

for i in res:

print(i)

for a,b in res:

print(a,b)