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  • python基础教程之第一部分day03-元组、字典、字符串

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-----元组-----
元组查询
1 a = (1,2,3,4)
2 print(a[1:2]) #(2,)
购物车练习(列表方法练习)
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 1 product_list=[
 2     ['Mac',9000],
 3     ['kindle',800],
 4     ['tesla',900000],
 5     ['python book',105],
 6     ['bike',2000],
 7 ]
 8 pubs_list = []
 9 save = input("please input money:")
10 if save.isdigit():
11     save = int(save)
12     while True:
13 
14         print("shopping info".center(50,"-"))
15         #、打印商品内容
16         for i,v in enumerate(product_list,1):
17             print(i,v)
18         choice = input("please input nums:")
19         #验证输入是否合法
20         if choice.isdigit():
21             choice = int(choice)
22             if choice > 0 and choice <= len(product_list):
23                 #将用户选择商品用p_iters取出
24                 p_iters = product_list[choice-1]
25                 # print(p_iters)
26                 #如果剩余钱足够,可以继续购买
27                 if p_iters[1] < save:
28                     pubs_list.append(p_iters)
29                     print(p_iters)
30                     save -= p_iters[1]
31                 else:
32                     print("余额不足 %s" % save)
33         elif choice == 'quit':
34             for j in pubs_list:
35                 # print(pubs_list)
36                 print("您购买的商品 :%s" % j)
37             print("购买商品剩余金额 :%s" % save)
38             break
39 
40         else:
41             print("Invalid input")
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-----字典-----

字典:是Python中唯一的映射类型,采用键值对的形式存储数据。
特点:1、字典是无序的,且键(key)可哈希 2、键唯一

不可变类型:整型,字符串,元祖
可变类型:列表,字典

字典的创建
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 1 a=list()  #列表创建
 2 print(a) #[]
 3 
 4 dic={'name':'dream'}
 5 print(dic) #{'name': 'dream'}
 6 
 7 dic1={}
 8 print(dic1) #{}
 9 
10 dic2=dict((('name','dream'),))
11 print(dic2) #{'name': 'dream'}
12 
13 dic3=dict([['name','dream'],])
14 print(dic3) #{'name': 'dream'}
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id方法使用
1 a = 100
2 print(id(a)) #94845938306592
3 b = a
4 print(id(b)) #94845938306592
5 b = 20
6 print(id(b)) #94457323938848
字典增加
1 dic1 = {'name':'dream'}
2 print(dic1) #{'name': 'dream'}
3 #setdefault,键存在,返回想用的键相应的值;,键不存在,在字典中添加新的键值对
4 ret = dic1.setdefault('age',20)
5 print(dic1)  #{'name': 'dream', 'age': 20}
6 print(ret) #20
字典的查询
1 dic2 = {'age': 20, 'name': 'dream'}
2 print(dic2['name']) #dream
显示列表中所有的键
1 print(dic2.keys()) #dict_keys(['age', 'name'])
2 print(list(dic2.keys())) #['name', 'age']
3 #显示列表中说有的值
4 print(list(dic2.values())) #[20, 'dream']
5 #显示列表中说有的键、值
6 print(list(dic2.items())) #[('name', 'dream'), ('age', 20)]
字典修改
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1 dic3 = {'age': 20, 'name': 'dream'}
2 dic3['name'] = 'rise'
3 print(dic3) #{'name': 'rise', 'age': 20}
4 #update
5 dic4 = {'age':18,'sex':'man'}
6 dic3.update(dic4)
7 print(dic3) #{'age': 18, 'sex': 'man', 'name': 'rise'}
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字典删除
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 1 dic5 = {'age': 18, 'sex': 'man', 'name': 'rise'}
 2 
 3 #del 删除键值对
 4 del dic5['age']
 5 print(dic5) #{'sex': 'man', 'name': 'rise'}
 6 #clear 清空字典
 7 dic5.clear()
 8 print(dic5) #{}
 9 
10 #pop 删除字典中指定键值对,并返回该键值对的值
11 ret = dic5.pop('name')
12 print(ret) #rise
13 print(dic5) #{'sex': 'man', 'age': 18}
14 #popitem 随机删除某组键值对,病以元祖方式返回值
15 ret = dic5.popitem()
16 print(ret) #('sex', 'man')
17 print(dic5) #{'name': 'rise', 'age': 18}
18 #删除整个字典
19 del dic5
20 print(dic5)
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字典初始化
1 dic6 = dict.fromkeys(['age', 'sex','name','rise'],'test')
2 print(dic6) #{'rise': 'test', 'sex': 'test', 'age': 'test', 'name': 'test'}
字典嵌套
复制代码
1 school = {
2     "teachers":{
3         'xiaowang':["高个子","长的帅"],
4         'xiaohu':["技术好","玩的好"]
5     },
6     "students":{
7         "zhangsan":["成绩好","爱讲笑话"]
8     }
9 }
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字典嵌套查询
1 print(school['teachers']['xiaohu'][0]) #技术好
2 print(school["students"]["zhangsan"][1]) #爱讲笑话
字典嵌套修改
1 school["students"]["zhangsan"][0] = "眼睛很好看"
2 print(school["students"]["zhangsan"][0]) #眼睛很好看
字典排序
1 dic = {6:'666',2:'222',5:'555'}
2 print(sorted(dic)) #[2, 5, 6]
3 print(sorted(dic.values())) #['222', '555', '666']
4 print(sorted(dic.items())) #[(2, '222'), (5, '555'), (6, '666')]
循环遍历
1 dic7 = {'name': 'rise', 'age': 18}
2 for i in dic7:
3     print(("%s:%s") % (i,dic7[i])) #name:rise age:18

-----字符串-----
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 1 a = "this is my progect"
 2 #重复输出字符串
 3 print(a*2) #重复2次输出 this is my progectthis is my progect
 4 #通过索引获取字符串
 5 print(a[3:]) #s is my progect
 6 #in 方法判度
 7 print('is' in a) #True
 8 #格式化输出字符串
 9 print('%s mode1' % a) #this is my progect mode1
10 
11 #字符串拼接
12 a = "this is my progect"
13 b = "test"
14 print("".join([a,b])) #this is my progecttest
15 
16 d = "this is my progect"
17 e = "test"
18 f = ""
19 print(f.join([d,e])) #this is my progecttest
20 
21 #字符串常用内置方法
22 a = "this is my progect"
23 #居中显示
24 print(a.center(50,'*')) #****************this is my progect****************
25 #统计 元素在字符串中重复次数
26 print(a.count("is")) #2
27 #首字母大写
28 print(a.capitalize()) #This is my progect
29 #以某个内容结尾字
30 print(a.endswith("ct")) #True
31 #以某个内容开头字
32 print(a.startswith("th")) #True
33 #调整空格数
34 a = "this\t is my progect"
35 print(a.expandtabs(tabsize=10)) #this       is my progect
36 #查找一个元素,返回元素索引值
37 a = "this is my progect"
38 print(a.find('is')) #2
39 a = "this is my progect{name},{age}"
40 print(a.format(name='dream',age=18)) #this is my progectdream,18
41 print(a.format_map({'name':'rise','age':20})) #this is my progectrise,20
42 print(a.index('s')) #3
43 #判度字符串时候包含数字
44 print("abc1234".isalnum()) #True
45 #检查是否数字
46 print('12345'.isdigit())#True
47 #检查字符串是否合法
48 print('123abc'.isidentifier()) #False
49 print(a.islower()) #True 判断是否全小写
50 print(a.isupper())
51 print('f    d'.isspace()) #是否包含空格
52 print("My Project".istitle()) #首字母大写 True
53 print
      



  
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