第一部分day03-元组、字典、字符串

-----元组-----
元组查询

 a = (1,2,3,4)
 print(a[1:2]) #(2,)

购物车练习(列表方法练习)

 product_list=[
     ['Mac',9000],
     ['kindle',800],
     ['tesla',900000],
     ['python book',105],
     ['bike',2000],
 ]
 pubs_list = []
 save = input("please input money:")
 if save.isdigit():
     save = int(save)
     while True:

         print("shopping info".center(50,"-"))
         #、打印商品内容
         for i,v in enumerate(product_list,1):
             print(i,v)
         choice = input("please input nums:")
         #验证输入是否合法
         if choice.isdigit():
             choice = int(choice)
             if choice > 0 and choice <= len(product_list):
                 #将用户选择商品用p_iters取出
                 p_iters = product_list[choice-1]
                 # print(p_iters)
                 #如果剩余钱足够，可以继续购买
                 if p_iters[1] < save:
                     pubs_list.append(p_iters)
                     print(p_iters)
                     save -= p_iters[1]
                 else:
                     print("余额不足 %s" % save)
         elif choice == 'quit':
             for j in pubs_list:
                 # print(pubs_list)
                 print("您购买的商品 :%s" % j)
             print("购买商品剩余金额 :%s" % save)
             break

         else:
             print("Invalid input")

-----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

 a=list()  #列表创建
 print(a) #[]

 dic={'name':'dream'}
 print(dic) #{'name': 'dream'}

 dic1={}
 print(dic1) #{}

 dic2=dict((('name','dream'),))
 print(dic2) #{'name': 'dream'}

 dic3=dict([['name','dream'],])
 print(dic3) #{'name': 'dream'}

id方法使用

 a = 100
 print(id(a)) #
 b = a
 print(id(b)) #
 b = 20
 print(id(b)) #

字典增加

 dic1 = {'name':'dream'}
 print(dic1) #{'name': 'dream'}
 #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
 ret = dic1.setdefault('age',20)
 print(dic1)  #{'name': 'dream', 'age': 20}
 print(ret) #

字典的查询

 dic2 = {'age': 20, 'name': 'dream'}
 print(dic2['name']) #dream

显示列表中所有的键

 print(dic2.keys()) #dict_keys(['age', 'name'])
 print(list(dic2.keys())) #['name', 'age']
 #显示列表中说有的值
 print(list(dic2.values())) #[20, 'dream']
 #显示列表中说有的键、值
 print(list(dic2.items())) #[('name', 'dream'), ('age', 20)]

字典修改

 dic3 = {'age': 20, 'name': 'dream'}
 dic3['name'] = 'rise'
 print(dic3) #{'name': 'rise', 'age': 20}
 #update
 dic4 = {'age':18,'sex':'man'}
 dic3.update(dic4)
 print(dic3) #{'age': 18, 'sex': 'man', 'name': 'rise'}

字典删除

 dic5 = {'age': 18, 'sex': 'man', 'name': 'rise'}

 #del 删除键值对
 del dic5['age']
 print(dic5) #{'sex': 'man', 'name': 'rise'}
 #clear 清空字典
 dic5.clear()
 print(dic5) #{}

 #pop 删除字典中指定键值对，并返回该键值对的值
 ret = dic5.pop('name')
 print(ret) #rise
 print(dic5) #{'sex': 'man', 'age': 18}
 #popitem 随机删除某组键值对，病以元祖方式返回值
 ret = dic5.popitem()
 print(ret) #('sex', 'man')
 print(dic5) #{'name': 'rise', 'age': 18}
 #删除整个字典
 del dic5
 print(dic5)

字典初始化

 dic6 = dict.fromkeys(['age', 'sex','name','rise'],'test')
 print(dic6) #{'rise': 'test', 'sex': 'test', 'age': 'test', 'name': 'test'}

字典嵌套

 school = {
     "teachers":{
         'xiaowang':["高个子","长的帅"],
         'xiaohu':["技术好","玩的好"]
     },
     "students":{
         "zhangsan":["成绩好","爱讲笑话"]
     }
 }

字典嵌套查询

 print(school['teachers']['xiaohu'][0]) #技术好
 print(school["students"]["zhangsan"][1]) #爱讲笑话

字典嵌套修改

 school["students"]["zhangsan"][0] = "眼睛很好看"
 print(school["students"]["zhangsan"][0]) #眼睛很好看

字典排序

 dic = {6:'',2:'',5:''}
 print(sorted(dic)) #[2, 5, 6]
 print(sorted(dic.values())) #['222', '555', '666']
 print(sorted(dic.items())) #[(2, '222'), (5, '555'), (6, '666')]

循环遍历

 dic7 = {'name': 'rise', 'age': 18}
 for i in dic7:
     print(("%s:%s") % (i,dic7[i])) #name:rise age:18

-----字符串-----

 a = "this is my progect"
 #重复输出字符串
 print(a*2) #重复2次输出 this is my progectthis is my progect
 #通过索引获取字符串
 print(a[3:]) #s is my progect
 #in 方法判度
 print('is' in a) #True
 #格式化输出字符串
 print('%s mode1' % a) #this is my progect mode1

 #字符串拼接
 a = "this is my progect"
 b = "test"
 print("".join([a,b])) #this is my progecttest

 d = "this is my progect"
 e = "test"
 f = ""
 print(f.join([d,e])) #this is my progecttest

 #字符串常用内置方法
 a = "this is my progect"
 #居中显示
 print(a.center(50,'*')) #****************this is my progect****************
 #统计 元素在字符串中重复次数
 print(a.count("is")) #
 #首字母大写
 print(a.capitalize()) #This is my progect
 #以某个内容结尾字
 print(a.endswith("ct")) #True
 #以某个内容开头字
 print(a.startswith("th")) #True
 #调整空格数
 a = "this\t is my progect"
 print(a.expandtabs(tabsize=10)) #this       is my progect
 #查找一个元素，返回元素索引值
 a = "this is my progect"
 print(a.find('is')) #
 a = "this is my progect{name},{age}"
 print(a.format(name='dream',age=18)) #this is my progectdream,18
 print(a.format_map({'name':'rise','age':20})) #this is my progectrise,20
 print(a.index('s')) #
 #判度字符串时候包含数字
 print("abc1234".isalnum()) #True
 #检查是否数字
 print(''.isdigit())#True
 #检查字符串是否合法
 print('123abc'.isidentifier()) #False
 print(a.islower()) #True 判断是否全小写
 print(a.isupper())
 print('f    d'.isspace()) #是否包含空格
 print("My Project".istitle()) #首字母大写 True
 print('my project'.upper()) #MY PROJECT
 print('my project'.lower()) #my project
 print('My project'.swapcase()) #mY PROJECT
 print('my project'.ljust(50,"-")) #my project----------------------------------------
 print('my project'.rjust(50,'-')) #----------------------------------------my project
 #去掉字符串空格与换行符
 print("     my project\n".strip()) #my project
 print('test')
 #替换
 print("my project project".replace('pro','test',1)) #my testject project
 #从右向左查找
 print("my project project".rfind('t')) #
 #以右为准分开
 print("my project project".rsplit('j',1)) #['my project pro', 'ect']
 print("my project project".title()) #My Project Project