日常Python 代码片段整理

1、简单的 HTTP Web 服务器

import socketserver
import http.serverPORT = 8000 handler = http.server.SimpleHTTPRequestHandler 
with socketserver.TCPServer(("", PORT), handler) as http: 
    print("Server Launch at Localhost: " + str(PORT)) 
    http.serve_forever()#在浏览器中输入http://127.0.0.1:8000/

2、单行循环List

mylist = [10, 11, 12, 13, 14]
print([i * 2 for i in mylist]) # [20, 22, 24, 26, 28]
print([i * 5 for i in mylist]) # [50, 55, 60, 65, 70]

3、更新字典

mydict = {1: "Python", 2: "JavaScript", 3: "Csharp"}
mydict.update({4: "Dart"})
print(mydict) # {1: 'Python', 2: 'JavaScript', 3: 'Csharp', 4: 'Dart'}

4、拆分多行字符串

string = "Data \n is encrpted \n by Python"
print(string)
# Output
# Data
# is encrpted
# by Python
splited = string.split("\n")
print(splited) # ['Data ', ' is encrpted ', ' by Python']

5、跟踪列表中元素的频率

import collections
def Track_Frequency(List):
    return dict(collections.Counter(List))
print(Track_Frequency([10, 10, 12, 12, 10, 13, 13, 14]))
# Output
# {10: 3, 12: 2, 13: 2, 14: 1}

6、不使用 Pandas 读取 CSV 文件

# 简单的类创建
import csv
with open("Test.csv", "r") as file:
    read = csv.reader(f)
    for r in read:
        print(row)
# 输出
# ['Sr', 'Name', 'Profession'] 
# ['1', '小猴子', '数据挖掘工程师'] 
# ['2', '云朵君', '算法工程师']

7、将列表压缩成一个字符串

mylist = ["I learn", "Python", "JavaScript", "Dart"]
string = " ".join(mylist)
print(string) # I learn Python JavaScript Dart

8、 获取列表中元素的索引

mylist = [10, 11, 12, 13, 14]
print(mylist.index(10)) # 0 
print(mylist.index(12)) # 2
print(mylist.index(14)) # 4

9、*arg 的魔法

def func(*arg): 
    num = 0 
    for x in arg: 
        num = num + x
print(num) # 600
func(100, 200, 300)

10、获取任何数据的类型

data1 = 123 
data2 = "Py" 
data3 = 123.443 
data4 = True 
data5 = [1, 2]

print(type(data1)) # <class 'int'> 
print(type(data2)) # <class 'str'> 
print(type(data3)) # <class 'float'> 
print(type(data4)) # <class 'bool'> 
print(type(data5)) # <class 'list'>

11、修改打印函数

print("顶级编程语言是 %r, %r 和 %r" % ('Py', 'Js', 'C#'))
# 输出
# 顶级编程语言是“Py”、“Js”和“C#”

12、字符串去大写

data1 = "ABCD" 
data2 = "Py" 
data3 = "Learn Coding"
print(data1.lower()) # abcd 
print(data2.lower()) # py 
print(data3.lower()) # learn coding

13、快捷变量交换方式

d1 = 25 
d2 = 50
d1, d2 = d2, d1
print(d1, d2) # 50 25

14、带分隔符打印

print("Py", "Js", "C#", sep="-") # Py-Js-C#
print("100", "200", "300", sep="x") # 100x200x300

15、获取网页 HTML 数据

# 使用 pip 安装请求的第一个安装请求导入请求
r = requests.get("https://www.baidu.com/s?wd=数据STUDIO ") 
print(r) # 显示整页html数据

16、获取数据占用内存

import sys
def memory(data):
    return sys.getsizeof(data)
print(memory(100)) # 28
print(memory("Pythonnnnnnn")) # 61

17、简单的类创建

class Employee:
    def __init__(self, empID):
        self.empID = empID
        self.name = "Haider"
        self.salary = 50000
    
    def getEmpData(self):
        return self.name, self.salary
emp = Employee(189345)
print(emp.getEmpData()) # ('Haider', 50000)

18、字符串乘法器

# 正常方式 
for x in range(5):
    print("C#")
    
# 更好的方式
print("C# "*5) # C# C# C# C# C#

19、链式比较

a = 5 
print(1 == a < 2) # False
print(2 < 3 < 6 > a) # True

20、数字化整数值

integer = 234553
digitz = [int(i) for i in str(integer)]
print(digitz) # [2, 3, 4, 5, 5, 3]

》》后续迭代