4.14作业 王萍
# 4.14作业，python中的列表# list=[],表达式
# 1.定义一个列表
# # 1.
# list1=["duoceshi","xian01","test",10086]
# print(list1) ['duoceshi', 'xian01', 'test', 10086]
# print(type(list1)) <class 'list'>
# 2.
# list()函数
# str1="duoceshi"
# list1=list(str1)
# # print(list1) ['d', 'u', 'o', 'c', 'e', 's', 'h', 'i']
# print(type(list1)) <class 'list'>
# 列表中常用的函数与用法
# 1.索引赋值
# list1=["duoceshi","xian01","test",10086]
# list1="hello"
# print(list1) ['hello', 'xian01', 'test', 10086]
# 2.切片赋值
# list1=["duoceshi","xian01","test",10086]
# list1="duoceshi"
# print(list1) ['duoceshi', 'xian01', 'd', 'u', 'o', 'c', 'e', 's', 'h', 'i']
# append()函数，在列表末尾添加一个元素，可以添加任何数据类型的元素
# list1=["duoceshi","xian01","test",10086]
# list1.append("hello")
# list1.append(1234)
# list1.append(["xiaozhang"])
# print(list1)
# extend()函数，连接两个列表，变成一个列表，且把所有元素整合到一个列表中，不能与int类型整合
# list1=["hello"]
# list2=["duoceshi"]
# list1.extend(list2)
# print(list1) ['hello', 'duoceshi']
# list1=["hello"]
# list2="1234"
# list1.extend(list2)
# print(list1) ['hello', '1', '2', '3', '4']
# list1=["hello"]
# list2=1234
# list1.extend(list2)
# print(list1) 'int' object is not iterable
# insert()函数,根据索引位置去添加元素到列表中
# list1=["duoceshi","xian01","test",10086]
# list1.insert(0,"hello")
# list1.insert(1,1234)
# list1.insert(2,["xiaozhang"])
# print(list1) ['hello', 1234, ['xiaozhang'], 'duoceshi', 'xian01', 'test', 10086]
# index()函数，查看的列表元素的索引值
# list1=["duoceshi","xian01","test",10086]
# index1=list1.index("xian01")
# print(index1) 1
# remove()函数，移除列表中的元素，就删除，根据列表value值删除
# 如果列表中有重复数据，则只删除第一次出现的数据
# list1=["duoceshi","xian01","test","xian01",10086]
# list1.remove("duoceshi")
# list1.remove("xian01")
# print(list1) ['test', 'xian01', 10086]
# del,是一个关键字，根据索引进行删除列表元素
# list1=["duoceshi","xian01","test","xian02",10086]
# del list1
# del list1
# print(list1) ['xian01']
# sort(),函数可以对列表进行排序
# 只会对全部是int或全部是str类型的进行升序排列
# 排列的顺序是根据ascii编码，排列的顺序是数字0-9，大写A-Z,小写a-z的升序排列
# list1=["duoceshi","xian01","test","10086"]
# list1.sort()
# print(list1) ['10086', 'duoceshi', 'test', 'xian01']
# list1=
# list1.sort(reverse=True)
# print(list1)
# 如果把列表进行降序排序则在sort()函数的参数reverse=True
# sorted()函数
# list1=["duoceshi","xian01","test","10086"]
# # list2=sorted(list1,reverse=True)降序
# list3=sorted(list1,reverse=False)
# # print(list2)降序['xian01', 'test', 'duoceshi', '10086']
# print(list3) 升序['10086', 'duoceshi', 'test', 'xian01']
# sort()与sorted()区别在于，前者作用是排序的动作，不会产生新的列表，后者排序之后会产生一个新的排序之后的列表
#
# reverse(),反转列表
# list1=
# list1.reverse()
# print(list1) ['hello', 'test', 4, 5, 2, 3, 1]
# 另外一种反转列表
# list1=
# print(list1[::-1]) ['hello', 'test', 4, 5, 2, 3, 1]
# pop(),删除列表中元素
# list1=["duoceshi","xian01","test","10086"]
# print(list1.pop(0)) duoceshi
# print(type(list1.pop(0))) <class 'str'>
# print(list1) ['test', '10086']
# 元组
# tuple1=()
# tuple1=("hello","xian01",1,["duoceshi"],10010)
# # print(tuple1) ('hello', 'xian01', 1, ['duoceshi'], 10010)
# print(type(tuple1)) <class 'tuple'> 数据类型为元组
# tuple2=("xian01",)
# # print(tuple2) ('xian01',)
# print(type(tuple2)) <class 'tuple'>
# 元组能否使用索引和切片,可以
# tuple1=("hello","xian01",1,["duoceshi",10086],10010)
# print(tuple1) xian01
# print(type(tuple1)) <class 'str'>
# print(tuple1) 10010
# print(type(tuple1)) <class 'int'>
# print(tuple1) ['duoceshi', 10086]
# print(type(tuple1)) <class 'list'>
# print(tuple1) ('hello', 'xian01', 1)
# tuple1="xiaozhang" 元组的值不能对他直接更改
# print(tuple1)
# tuple1.insert(0,"xiaozhang") 元组的值不能对他直接更改
# print(tuple1)
# tuple1=("hello","xian01",1,["duoceshi",10086],10010)
# list1=list(tuple1)
# list1="xiaozhang"
# tuple2=tuple(list1)
# print(tuple2) ('hello', 'xiaozhang', 1, ['duoceshi', 10086], 10010)
# tuple1=("hello","xian01",1,["duoceshi",10086],10010)
# tuple1="dcs"
# print((tuple1)) ('hello', 'xian01', 1, ['dcs', 10086], 10010)
# 元组的迭代，需要用到for循环对元组进行迭代取值
# tuple1=("hello","xian01",1,["duoceshi",10086],10010)
# for i in tuple1:
# print(i) 迭代取值：hello xian01 1 ['duoceshi', 10086] 10010
# # 字典
# dict1={}
# dict1={"name":"xiaozhang","age":18}
# # print(dict1) {'name': 'xiaozhang', 'age': 18}
# print(type(dict1)) <class 'dict'>
# 定义字典用dict()函数
# test=[("name","xiaozhang"),("age",18)]
# dict1=dict(test)
# # print(dict1) {'name': 'xiaozhang', 'age': 18}
# print(type(dict1)) <class 'dict'>
# 添加一个键值对
# dict1={"name":"xiaozhang","age":18}
# dict1["sex"]="man"
# print(dict1) {'name': 'xiaozhang', 'age': 18, 'sex': 'man'}
# 取出字典中的键,通过for循环去遍历字典中的所有的键
# 没有在for循环中加入修饰函数，默认取的是键
# dict1={"name":"xiaozhang","age":18}
# for i in dict1:
# print(i) name age
# 加入修饰函数keys(),取的是键
# dict1={"name":"xiaozhang","age":18}
# for i in dict1.keys():
# print(i) name,age
# 加入修饰函数values(),取的是值
# dict1={"name":"xiaozhang","age":18}
# for i in dict1.values():
# print(i) xiaozhang,18
# 取出字典中具体的值，只能通过键才能取键对应的值
# dict1={"name":"xiaozhang","age":18}
# # print(dict1["name"]) xiaozhang
# print(dict1["age"]) 18
# setdefault()函数，给字典中添加键值对
# dict1={"name":"xiaozhang","age":18}
# dict1.setdefault("sex","man")
# # print(dict1) {'name': 'xiaozhang', 'age': 18, 'sex': 'man'}
# 删除字典中的元素，根据键来删除值
# dict1={"name":"xiaozhang","age":18}
# del dict1["name"]
# print(dict1) {'age': 18}
# 删除整个字典
# dict1={"name":"xiaozhang","age":18}
# del dict1
# print(dict1) name 'dict1' is not defined
# pop()函数，根据键来删除对应的值
# dict1={"name":"xiaozhang","age":18}
# dict1.pop("name") 在字典中pop()函数需要写入建，不能为空，xiaozhang,可以吧删除的值打印处理
# print(dict1) {'age': 18}
# clear()
# dict1 = {"name": "xiaozhang", "age": 18}
# dict1.clear()
# print(dict1) {}清空
# dict1 = {"name": "xiaozhang", "age": 18}
# for i in dict1:
# print(i,dict1) name xiaozhang age 18
# items(),取键与值
# dict1 = {"name": "xiaozhang", "age": 18}
# for k,v in dict1.items():
# print(k,v) name xiaozhangage 18
# get()
# dict1 = {"name": "xiaozhang", "age": 18}
# # print(dict1.get("name")) xiaozhang
# # age1=dict1.get("age")
# # print(age1) 18
# print(dict1.get("wangping")) None
#
# fromkeys(),定义初始化的字典
# dict1={}.fromkeys(["name","age"])
# # dict1["name"]="xiaozhang"
# # dict1["age"]=18
# # print(dict1)
# dict1={}.fromkeys(("name","age"),"xiaozhang")
# print(dict1) {'name': 'xiaozhang', 'age': 'xiaozhang'}
# __contains__(),私有函数，判断是否含有某个键，true/False
# dict1 = {"name": "xiaozhang", "age": 18}
# # print(dict1.__contains__("name")) True
# # print(dict1.__contains__("name1")) False
#
# if dict1.__contains__("name1")is True:
# print("判断成功")
# else:
# dict1.setdefault("name1")
# print(dict1) {'name': 'xiaozhang', 'age': 18, 'name1': None}
# popitem()
# dict1={"name":"xiaozhang","age":18}
# pop=dict1.popitem()
# print(dict1)
# print(pop)
# print(type(pop))
# update(),利用一个字典更新另外一个
# dict1 = {"name": "xiaozhang", "age": 18}
# dict2={"sex":"man"}
# dict1.update(dict2)
# print(dict1)
# 集合，可变集合set,不可变集合frozenset,去重
# name="xian01a"
# set1=set(name)
# # set1.clear()
# # set1.pop()
# # set1.remove("x")
# # set1.add("zhang")
# print(set1)
# print(type(set1))
#
# name="xian01"
# set1=frozenset(name)
# set2=set1.copy()
# print(set2)
# print(set1)
# print(type(set1))
# list1=
# # set1=set(list1)
# # list2=list(set1)
# # print(list2)
#
# list2=[]
# for i in set(list1):
# list2.append(i)
# print(list2)
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