4.14 Python
# python中的列表'''
列表用list表示
表达式为list = []中括号表示列表
'''
# 1.定义一个列表
# 第一种方法
# list1 = ["xiaowang","xiaozhang","banli",320]
# print(list1) #['xiaowang', 'xiaozhang', 'banli', 320]
# print(type(list1)) #<class 'list'>
# 第二种方法
# list1 = ["xiaowang","xiaozhang","banli",320]
# str1 = "xiaozhang"
# list1 = list(str1)
# print(list1) #['x', 'i', 'a', 'o', 'z', 'h', 'a', 'n', 'g']
# print(type(list1)) #<class 'list'>
# 列表中常用的函数和用法
# 1.索引赋值
# list1 = ["xiaohei","xiaozhang","banli",320]
# list1 = "xiaowang"
# print(list1) #['xiaohei', 'xiaowang', 'banli', 320]
# 2.切片赋值
# list1 = ["xiaohei","xiaozhang","banli",320]
# list1 = "wangqian"
# print(list1) #['xiaohei', 'xiaozhang', 'w', 'a', 'n', 'g', 'q', 'i', 'a', 'n']
# append()函数，在末尾添加一个元素，可以添加任何数据类型的元素
# list1 = ["xiaohei","xiaozhang","banli",320]
# list1.append("wangqian")
# print(list1) #['xiaohei', 'xiaozhang', 'banli', 320, 'wangqian']添加字符串str
# list1.append("4321")
# print(list1) #['xiaohei', 'xiaozhang', 'banli', 320, '4321'] 添加整型int
# list1.append(["wangqian"])
# print(list1) #['xiaohei', 'xiaozhang', 'banli', 320, ['wangqian']]添加列表list
# extend（）函数，连接两个列表，变成一个列表注：不能用int类型进行整合
# list1 = ["wangqian"]
# list2 = ["xiaohei"]
# list1.extend(list2)
# print(list1) #['wangqian', 'xiaohei']
# list1 = ["banli"]
# list2 = ["415"]
# list1.extend(list2)
# print(list1) #['banli', '415']
# insert()函数，根据索引位置去添加元素到列表中
# list1 = ["xiaohei","xiaowang","banli",415]
# list1.insert(0,"wang")
# print(list1) #['wang', 'xiaohei', 'xiaowang', 'banli', 415] 插入数据类型为字符串str
# list1.insert(1,320)
# print(list1) #['xiaohei', 320, 'xiaowang', 'banli', 415] 插入数据列表为整型int
# list1.insert(2,["heizai"])
# print(list1) ['xiaohei', 'xiaowang', ['heizai'], 'banli', 415]插入数据类型为list
# index()函数，查看的列表元素的索引值
# list1 = ["xiaohei","xiaowang","banli",415]
# index1 = list1.index("xiaohei")
# print(index1) # 0
# remove()函数，移除列表中的元素，根据列表value值删除
# list1 = ["xiaohei","xiaowang","banli","xiaohei",415]
# list1.remove("xiaowang")
# print(list1) #['xiaohei', 'banli', 'xiaohei', 415]
# list1.remove("xiaohei")
# print(list1) #['xiaowang', 'banli', 'xiaohei', 415]如果列表中有重复出现，只删除第一次出现的数据
# del,是一个关键字，根据索引进行删除列表元素
# list1 = ["xiaohei","xiaowang","banli","xiaohei",415]
# del list1
# print(list1) #['xiaowang', 'banli', 'xiaohei', 415]
# del list1
# print(list1) #['xiaohei']
# sotr()函数可以对列表进行排序
# 只会对全部是int或str类型的进行升序排序，根据ascii编码，数字0-9，大写A-Z,小写a-z
# list1 = ["xiaohei","wang","banli","415"]
# list1.sort()
# print(list1) #['415', 'banli', 'wang', 'xiaohei']
# list1 = ["xiaohei","Wang","banli","415"]
# list1.sort()
# print(list1) #['415', 'Wang', 'banli', 'xiaohei']
# list1 =
# list1.sort(reverse=True)
# print(list1) #
# 对表进行降序排列在sort()函数的参数加上reverse=True
# sorted()函数
# list1 = ["xiaohei", "Wang", "banli", "415"]
# list2 = sorted(list1,reverse=True)
# print(list2) #['xiaohei', 'banli', 'Wang', '415'] 降序排列
# list3 = sorted(list1,reverse=False)
# print(list3) #['415', 'Wang', 'banli', 'xiaohei'] 升序排列
# reverse()函数列表反转
# list1 =
# list1.reverse()
# print(list1) #['heizai', 'banli', 9, 2, 8, 6, 4, 1]
# 第二种方法
# print(list1[::-1]) #['heizai', 'banli', 9, 2, 8, 6, 4, 1]
# pop()函数删除列表中的元素
# list1 = ["xiaohei", "Wang", "banli", "415"]
# print(list1.pop(0)) #xiaohei
# print(type(list1.pop(0))) #<class 'str'>
# python 中的元组
# 元组（tuple） 表达为tuple1 = ()
# tuple1 = ("xiaohei", "Wang",3,["banli"], "415")
# print(tuple1) #('xiaohei', 'Wang', 3, ['banli'], '415')
# print(type(tuple1)) #<class 'tuple'> 数据类型为元组
# tuple2 = ("xiaohei")
# print(tuple2) #xiaohei
# print(type(tuple2)) #<class 'str'>
# 元组中的索引和切片
# tuple1 = ("xiaohei", "Wang",3,["banli"], "415")
# print(tuple1) #Wang
# print(type(tuple1)) #<class 'str'>
# print(tuple1) #415
# print(type(tuple1)) #<class 'str'>
# print(tuple1) #['banli']
# print(type(tuple1)) #<class 'list'>
# tuple1 = "xiaowang"
# print(tuple1) #元组的值不能直接更改
# tuple1.insert(0,"xiaowang")
# print(tuple1) #元组的值不能直接更改
# tuple1 = ("xiaohei", "Wang",3,["banli"], "415")
# list1 = list(tuple1)
# list1 = "xiaowang"
# tuple2 = tuple(list1)
# print(tuple2) #('xiaohei', 'xiaowang', 3, ['banli'], '415')
# tuple1 = ("xiaohei", "Wang",3,["banli"], "415")
# tuple1 = "wangqian"
# print(tuple1) #'xiaohei', 'Wang', 3, ['wangqian'], '415')
#元组的迭代 需要for循环对元组进行迭代取值
# tuple1 = ("xiaohei", "Wang",3,["banli"], "415")
# for i in tuple1:
# print(i)
# python中的字典
# 定义字典的常规方法
# dict1 = {"name":"banli","age":1}
# print(dict1) #{'name': 'banli', 'age': 1}
# print(type(dict1)) #<class 'dict'>
# 定义字典用dict()函数
# test = [("name","banli"),("age",1)]
# dict1 = dict(test)
# print(dict1) #{'name': 'banli', 'age': 1}
# print(type(dict1)) #<class 'dict'>
# 添加一个键值对
# dict1 = {"name":"banli","age":1}
# dict1["sex"] = "man"
# print(dict1) #{'name': 'banli', 'age': 1, 'sex': 'man'}
# 取出字典中的键 通过for循环字典中所有的键
# dict1 = {"name":"banli","age":1}
# for i in dict1:
# print(i) #name,age
# 加入修饰函数keys()函数 取的是键
# dict1 = {"name":"banli","age":1}
# for i in dict1.keys():
# print(i) #name,age
# 加入修饰函数valuse()函数 取的是字典中的值
# dict1 = {"name":"banli","age":1}
# for i in dict1.values():
# print(i) #banli,1
# 取出字典中具体的值
# dict1 = {"name":"banli","age":1}
# print(dict1["name"]) #bamli
# print(dict1["age"]) #1
# setdefault()函数给字典中添加键值对
# dict1 = {"name":"banli","age":1}
# dict1.setdefault("sex","man")
# print(dict1) #{'name': 'banli', 'age': 1, 'sex': 'man'}\
# 删除字典中的元素，根据键来删除值
# dict1 = {"name":"banli","age":1}
# del dict1["name"]
# print(dict1) # {'age': 1}
# 删除整个字典
# dict1 = {"name":"banli","age":1}
# del dict1
# print(dict1) #name 'dict1' is not defined 字典全部删除
# pop()函数,根据键来删除对应的值
# dict1 = {"name":"banli","age":1}
# dict1.pop("name")
# print(dict1) #{'age': 1}
# clear()清空字典所有数据
# dict1 = {"name":"banli","age":1}
# dict1.clear()
# print(dict1) #{}
# 通过for循环取字典中的键与值
# dict1 = {"name":"banli","age":1}
# for i in dict1:
# print(i,dict1) #name banli,age 1
# 通过inems()取字典中的键与值
# dict1 = {"name":"banli","age":1}
# for k,v in dict1.items():
# print(k,v) #name banli,age 1
# 通过get()函数，取键的值，如果键不在字典中，则返回None
# dict1 = {"name":"banli","age":1}
# print(dict1.get("name")) #banli
# age1 = dict1.get("age")
# print(age1) #1
# print(dict1.get("zhangshifu")) #None
# fromkeys()函数，定义一个初始化的字典
# dict1 = {}.fromkeys(["name","age"]) #{'name': None, 'age': None}
# dict1["name"] = "banli"
# dict1["age"] = 1
# print(dict1)
# dict1 = {}.fromkeys(("name","age"),"bamli")
# print(dict1) #{'name': 'bamli', 'age': 'bamli'}
# __contains__()函数
# dict1 = {"name":"banli","age":1}
# print(dict1.__contains__("name")) #True
# print(dict1.__contains__("name1")) #False
# if dict1.__contains__("name") is True:
# print("判断成功")
# else:
# dict1.setdefault("name1")
# print(dict1)
# popitem()函数删除字典中的键值，同时删除键与值，删除最后的
# dict1 = {"name": "banli", "age": 1}
# pop = dict1.popitem()
# print(dict1) #{'name': 'banli'} 删除完剩下的
# print(pop) #('age', 1) 已经删除了的
# print(type(pop)) #<class 'tuple'>
# update()函数，利用一个字典更新另一个字典
# dict1 = {"name": "banli", "age": 1}
# dict2 = {"sex":"man"}
# dict1.update(dict2)
# print(dict1) #{'name': 'banli', 'age': 1, 'sex': 'man'}
# python中的集合
# name = "xiaowang"
# set1 = set(name)
# set1.clear()
# print(set1) #set()清除集合中的数据
# set1.pop()
# print(set1) #{'x', 'a', 'w', 'o', 'g', 'i'} 随机删除集合中的某个元素
# set1.remove("x")
# print(set1) #{'w', 'o', 'n', 'g', 'i', 'a'}删除集合中的x元素
# set1.add("wang")
# print(set1) #{'g', 'o', 'n', 'a', 'w', 'wang', 'i', 'x'}添加wang到集合中
# name = "xiaohei"
# set1 = frozenset(name)
# set2 = set1.copy()
# print(set2) #frozenset({'o', 'i', 'h', 'a', 'e', 'x'})
# print(type(set2)) #<class 'frozenset'>
list1 = [1,1,3,5,7,7,9]
set1 = set(list1)
list2 = list(set1)
print(list2) #
list2 = []
for i in set(list1):
list2.append(i)
# print(list2)
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