Python模块列表字典
Python模块列表字典
一、模块
sys
#!/usr/bin/env Python
# -*- coding:utf-8 -*-
import sys
# print(sys.path) #打印环境变量
print(sys.argv)
os
#!/usr/bin/env python
# -*- coding:utf-8 -*-
import os
# cmd_res = os.system("dir") #执行命令，不保存结果
cmd_res = os.popen("dir").read()
print("-->",cmd_res)
os.mkdir("new_dir")
二、数据类型
1、数字
int（整型）
在32位机器上，整数的位数为32位，取值范围为-2**31～2**31-1，即-2147483648～2147483647
在64位系统上，整数的位数为64位，取值范围为-2**63～2**63-1，即-9223372036854775808～9223372036854775807
long（长整型）
跟C语言不同，Python的长整数没有指定位宽，即：Python没有限制长整数数值的大小，但实际上由于机器内存有限，我们使用的长整数数值不可能无限大。
注意，自从Python2.2起，如果整数发生溢出，Python会自动将整数数据转换为长整数，所以如今在长整数数据后面不加字母L也不会导致严重后果了。
float（浮点型）
浮点数用来处理实数，即带有小数的数字。类似于C语言中的double类型，占8个字节（64位），其中52位表示底，11位表示指数，剩下的一位表示符号。
complex（复数）
复数由实数部分和虚数部分组成，一般形式为x＋yj，其中的x是复数的实数部分，y是复数的虚数部分，这里的x和y都是实数。
2、布尔值
真或假
1或0
三、三元运算
result = 值1 if 条件 else 值2
a,b,c=1,3,5
d=a if a>b else c
四、进制
二进制，01
八进制，01234567
十进制，0123456789
十六进制，0123456789ABCDEF
五、列表
1、创建列表
names = ["hhh","aaa","bbb",["kkk","jjj"],"ccc","bbb"]
或
names = list(["hhh","aaa","bbb",["kkk","jjj"],"ccc","bbb"])
2、索引
print(names)
print(names[0],names[2])
3、切片
print(names[1:3])
print(names[3])
print(names[-2])
print(names[-2:])
print(names[:3])
4、追加
names.append("ddd") #末尾增加
names.insert(1,"eee") #按位置增加
names[2] = "fff" #替换
5、删除
names.remove("fff")
# del names[1] = names.pop(1)
names.pop(1)
print(names)
6、长度
print(names.index("ccc"))
print(names.count("bbb"))
names.clear() #清空
names.reverse() #反转
names.sort() #排序
7、循环
for i in names:
print(i)
8、复制
import copy
name2 = names.copy()
names2 = copy.deepcopy(names) #深复制，占用
print(names)
print(name2)
9、包含
names2 = [1,2,3,4]
names.extend(names2)
print(names,names2)
六、元组
元组其实跟列表差不多，也是存一组数，只不过它一旦创建，便不能再修改，所以又叫只读列表
它只有2个方法，一个是count,一个是index
ages = (11, 22, 33, 44, 55)
或
ages = tuple((11, 22, 33, 44, 55))
七、程序：购物车程序
需求:
1、启动程序后，让用户输入工资，然后打印商品列表
2、允许用户根据商品编号购买商品
3、用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒
4、可随时退出，退出时，打印已购买商品和余额
#!/usr/bin/env python
# -*- coding:utf-8 -*-
product_list = [
('Iphone',5800),
('Mac Pro',9800),
('Bike',800),
('Watch',10600),
('Coffee',31),
('Alex Python',120),
]
shopping_list = []
salary = input("Input your salary:")
if salary.isdigit():
salary = int(salary)
while True:
for index,item in enumerate(product_list):
# print(product_list.index(item),item)
print(index,item)
user_choice = input("选择要买嘛？>>>:")
if user_choice.isdigit():
user_choice = int(user_choice)
if user_choice < len(product_list) and user_choice >=0:
p_item = product_list[user_choice]
if p_item[1] <= salary: #买得起
shopping_list.append(p_item)
salary -= p_item[1]
print("Added %s into shopping cart,your current balance is \033[31;1m%s\033[0m" %(p_item,salary))
else:
print("\033[41;1m你的余额只剩[%s]啦，还买个毛线\033[0m" %salary)
else:
print("product code [%s] is not exist!"% user_choice)
elif user_choice == 'q':
print("----------shopping list------------")
for p in shopping_list:
print(p)
print("Your current balance:",salary)
exit()
else:
print("invalid option")
八、字符串
#!/usr/bin/env python
# -*- coding:utf-8 -*-
name = "my \tname is {name} and i am {year} old"
print(name.capitalize()) #首字母
print(name.count("a"))
print(name.center(50,"-"))
print(name.endswith("ex")) #以什么结尾
print(name.expandtabs(tabsize=30))
print(name[name.find("name"):])
print(name.format(name='alex',year=23))
print(name.format_map({'name':'alex','year':12}))
print('ab23'.isalnum())
print('abA'.isalpha())
print('1A'.isdecimal()) #十进制
print('a 1A'.isidentifier()) #判读是不是一个合法的标识符
print('a 1A'.islower())
print('33.33'.isnumeric())
print('My Name Is'.istitle())
print('My Name Is'.isprintable())
print('My Name Is'.isupper())
print(''
'+'.join(['1','2','3']))
print(name.ljust(50,'*'))
print(name.rjust(50,'-'))
print('Alex'.lower())
print('Alex'.upper())
print('\nAlex'.lstrip())
print('\nAlex\n'.rstrip())
print(' \nAlex\n'.strip())
p = str.maketrans("abcdef",'123456')
print("alex li".translate(p))
print('alex li'.replace('l','L',1))
print('alex lil'.rfind('l'))
print('1+2+3+4'.split('+'))
print('1+2\n+3+4'.splitlines())
print('Alex Li'.swapcase())
print('lex li'.title())
print('lex li'.zfill(50))
九、字典（无序的）
字典一种key - value 的数据类型，使用就像我们上学用的字典，通过笔划、字母来查对应页的详细内容。
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#key-value
'''
av_catalog = {
"欧美":{
"www.youporn.com": ["很多免费的,世界最大的","质量一般"],
"www.pornhub.com": ["很多免费的,也很大","质量比yourporn高点"],
"letmedothistoyou.com": ["多是自拍,高质量图片很多","资源不多,更新慢"],
"x-art.com":["质量很高,真的很高","全部收费,屌比请绕过"]
},
"日韩":{
"tokyo-hot":["质量怎样不清楚,个人已经不喜欢日韩范了","听说是收费的"]
},
"大陆":{
"1024":["全部免费,真好,好人一生平安","服务器在国外,慢"]
}
}
av_catalog["大陆"]["1024"][1] = "可以在国内做镜像"
av_catalog.setdefault("taiwan",{"www.baidu.com":[1,2]})
print(av_catalog)
'''
info = {
'stu1101': "TengLan Wu",
'stu1102': "LongZe Luola",
'stu1103': "XiaoZe Maliya",
}
for i in info:
print(i,info[i])
for k,v in info.items():
print(k,v)
# b = {
# 'stu1101':"Alex",
# 1:3,
# 2:5
# }
# info.update(b)
# print(info)
# c = dict.fromkeys([6,7,8],[1,{"name":"alex"},444])
# print(c)
# c[7][1]['name'] = "Jack Chen" #共用一个内存
# print(c)
# print(info.items())
# print(info)
# # print(info["stu1101"])
# print(info.get('stu1103'))
#
# print('stu1103' in info) #info.has_key("1103") in py2.x
# info["stu1101"] = "武藤兰"
# info["stu1104"] = "CangJingkong"
#del
# del info["stu1101"]
# info.pop("stu1101")
# info.popitem()
# print(info)
十、三级菜单
#!/usr/bin/env python
# -*- coding:utf-8 -*-
data = {
'北京':{
"昌平":{
"沙河":["oldboy","test"],
"天通苑":["链家地产","我爱我家"]
},
"朝阳":{
"望京":["奔驰","陌陌"],
"国贸":{"CICC","HP"},
"东直门":{"Avent","飞信"},
},
"海淀":{},
},
'山东':{
"德州":{},
"青岛":{},
"济南":{}
},
'广东':{
"东莞":{},
"常熟":{},
"佛山":{},
},
}
exit_flag = False
while not exit_flag:
for i in data:
print(i)
choice = input("选择进入1>>:")
if choice in data:
while not exit_flag:
for i2 in data[choice]:
print("\t",i2)
choice2 = input("选择进入2>>:")
if choice2 in data[choice]:
while not exit_flag:
for i3 in data[choice][choice2]:
print("\t", i3)
choice3 = input("选择进入3>>:")
if choice3 in data[choice][choice2]:
for i4 in data[choice][choice2][choice3]:
print("\t\t",i4)
choice4 = input("最后一层，按b返回>>:")
if choice4 == "b":
pass
elif choice4 == "q":
exit_flag = True
if choice3 == "b":
break
elif choice3 == "q":
exit_flag = True
if choice2 == "b":
break
elif choice2 == "q":
exit_flag = True
十一、作业
购物车
用户入口：
1、商品信息存在文件里
2、已购商品，余额记录
商家入口：
2、可以添加商品，修改商品价格
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# 用户或者是商家
# 用户-登陆信息-卡里剩多少钱-打开商品列表-选择商品-打印已购商品，余额记录
# 商家-登陆信息-添加商品/修改商品价格-存入文件
user_info = {"zhangsan":[333333,30000],"lisi":[444444,40000],"wangwu":[555555,50000]}
shopper_info = {"hhh":666666}
user = input("user:")
password = input("password:")
shopping_list = []
product_list = open("product_list.txt").readlines()
if user in user_info and int(user_info[user][0]) == int(password):
salary = int(user_info[user][1])
print("Welcome %s to our shopping center!Your salary is %s" % (user, salary))
while True:
for k, v in enumerate(product_list):
print(k, v)
choice = input("Which product do you want to select?")
shopping_list.append(product_list[int(choice)])
shop_price = int(product_list[int(choice)].split(":")[1])
salary -= shop_price
print("Your shopping_list is %s and your salary is %s" % (shopping_list, salary))
choice2 = input("Do you want to continue to shopping?")
if choice2 == "n":
print("Welcome to you next time!Your shopping_list is %s and your salary is %s" % (shopping_list, salary))
break
elif choice2 == "y":
pass
elif user in shopper_info and int(shopper_info[user]) == int(password):
while True:
print("1 add product\n""2 modify price")
choice3 = input("What do you want to do?")
if choice3 == "1":
product = input("Which product do you want to add?")
price = input("This product's price is?")
product_info = "\n"+product+":"+price
with open("product_list.txt",'a+') as f:
f.write(product_info+'\n')
choice4 = input("Do you want to continue?")
if choice4 == "y":
pass
elif choice4 == "n":
break
elif choice3 == "2":
for k, v in enumerate(product_list):
print(k, v)
choice5 = input("Which product do you want to modify?")
new_price = input("This product's price is modify to?")
old_price = product_list[int(choice5)].split(":")[1]
file_data = ""
with open("product_list.txt","r") as f:
for line in f:
if old_price in line:
line = line.replace(old_price,new_price) + '\n'
file_data += line
with open("product_list.txt","w") as f:
f.write(file_data)
choice6 = input("Do you want to continue?")
if choice6 == "y":
pass
elif choice6 == "n":
break
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