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)) #94845938306592
b = a
print(id(b)) #94845938306592
b = 20
print(id(b)) #94457323938848

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) #20

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:'666',2:'222',5:'555'}
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")) #2
#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	 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')) #2
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')) #3
#判度字符串时候包含数字
print("abc1234".isalnum()) #True
#检查是否数字
print('12345'.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
".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')) #17
#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