Python基础

1、进制之间转换

# 10进制转为2进制
print(bin(5))
#10进制转为8进制
print(oct(9))
#10进制转为16进制
print(hex(15))
print("------2-----")
#2进制转为8进制
print(oct(int('101',2)))
#2进制转为10进制
print(int('101',2))
#2进制转为16进制
print(hex(int('101',2)))
print("-----8------")
#8进制转为2进制
print(bin(int('0o11',8)))
#8进制转为10进制
print(int('0o11',8))
#8进制转为16进制
print(hex(int('0o11',8)))
print("-----16------")
#16进制转为2进制
print(bin(int('0x9',16)))
#16进制转为10进制
print(int('0x9',16))
#16进制转为8进制
print(oct(int('0x9',16)))

2、数组、字典、元组转换

# float专int
f01=3.1415926
print(int(f01))
list01=[1,2,3,4]
#数组专元组
print(tuple(list01))
tuple01=(1,2,3,4)
# 元组专数组
print(list(tuple01))
print("数组转为set")
print(set(list01))
print("元组转为set")
print(set(tuple01))
# 字典
dict01={"name":"zs","age":"18"}
print("字典转为set")
print(set(dict01))
print("字典转为list")
print(list(dict01))
print(list(dict01.values()))

3、取出字典中的值

student = {'stuno':'1001','age':'18','banji':'软件01'}
for key in student:
    print(key,'==',student[key])

print("只循环值")
for value in student.values():
    print(value)

print("同时循环key,value")
for key,value in student.items():
    print("key=",key,",value=",value)

4、函数

def hell_fun(name,age):
    return '{}{}你好'.format(name,age)
def hello_pp(greeting,name='zhangsan'):
    return '{},{}:你好'.format(greeting,name)

print(hell_fun("zd",23))
print(hello_pp('nihao'))
print(hello_pp('nihao','zs'))

def student_info(*args,**kwargs):
    print(args)
    print(kwargs)

courses = ['js','css','php']
info = {'name':'zs','age':'18'}
student_info(courses,info)
student_info(*courses,**info)

def foo(x,*args,a=4,**kwargs):
    print(x)
    print(args)
    print(a)
    print(kwargs)

foo(1,(5,6,7,8),{'name':'zs','age':'18'})
foo(1,*(5,6,7,8),**{'name':'zs','age':'18'})

add = lambda x,y:x+y
add01 = lambda *args:sum(args)
print(add01(1,56,35,1,1,23))
print(add(1,3))

5、获得当前时间以及文件名

import time
import os
report_time = time.strftime("%Y%m%d%H%M%S",time.localtime())
print(report_time+"_"+os.path.basename(__file__))

6、从某个序列中取出数据

import random
courses = ['js','java','css','html','php','go']
random_course = random.choice(courses)
print(random_course)

7、生成随机字符串

import string

red_str = ''.join(random.choice(string.ascii_uppercase+string.ascii_lowercase+string.digits)for _ in range(8))
print(red_str)

 8、读取文件

try:
    with open('test.log') as fh:
        fille_data = fh.read()
    print(fille_data)
except FileNotFoundError:
    print('This data file is missing.')
except PermissionError:
    print('This is not allowed.')
except Exception as err:
    print('Some other error occurred:',str(err))

常见错误

 

 常用的字符串方法

 

 os模块

9、创建定义类

class Car(object):
    def __init__(self,make,model,year):
        self.make = make
        self.model = model
        self.year = year


    def get_des(self):
        long_name = str(self.year) + '' + self.make + ' '+self.model
        return long_name.title()

my_new_car = Car('mini','a4',2016)
print(my_new_car.get_des())

if __name__ == '__main__':
    my_new_car = Car('mini','a4',2016)
    print(my_new_car.get_des())

10、继承

class Car(object):
    def __init__(self,make,model,year):
        self.make = make
        self.model = model
        self.year = year

    def get_des(self):
        long_name = str(self.year) + '' + self.make + ' '+self.model
        return long_name.title()

class ElectricCar(Car):
    def __init__(self,make,model,year,battery):
        super().__init__(make,model,year)
        self.battery = battery
        
    def des_battery(self):
        print(self.battery)

my_tesla =  ElectricCar('mini','model 4',2016,'20万')
print(my_tesla.get_des())
my_tesla.des_battery()

11、重写

class Car(object):
    def __init__(self,make,model,year):
        self.make = make
        self.model = model
        self.year = year

    def get_des(self):
        long_name = str(self.year) + '' + self.make + ' '+self.model
        return long_name.title()

class ElectricCar(Car):
    def __init__(self,make,model,year,battery):
        super().__init__(make,model,year)
        self.battery = battery

    def des_battery(self):
        print(self.battery)
    #重写父类get_des()
    def get_des(self):
        long_name = str(self.year) + ' ' + self.make + ' '+self.model+' battery:'+self.battery
        return long_name.title()


my_tesla =  ElectricCar('mini','model 4',2016,'20万')
print(my_tesla.get_des())
my_tesla.des_battery()

12、下划线 ,双下划线的作用

• 变量名如果以__开头，就变成了一个私有变量（private）
• 变量名如果以_开头，这样的变量可以被外部所访问，但是， 按照约定俗成的规定，当你看到这样的变量时，意思就 是，“虽然我可以被访问，但是，请把我视为私有变量，不要随意访问”
• 变量名类似__xxx__的，也就是以双下划线开头，并且以双 下划线结尾的，系统自定义名字，不建议占用

13、导入类

导入单个类

from car import Car

my_new_car = Car('benchi','a4',2016)
print(my_new_car.get_des())

从一个模块中导入多个类

from car3 import Car,ElectricCar

my_new_car = Car('benchi','a4',2016)
print(my_new_car.get_des())

my_tesla =  ElectricCar('mini','model 4',2016,'20万')
print(my_tesla.get_des())
my_tesla.des_battery()

从一个模块中导入所有类

from model_name  import *

导入多个模块

from model_name_01  import *
from model_name_02  import *
from model_name_03  import *

14、函数运行时长计时器

import time
import random

def time_count(func):
    def wrap(*args,**kwargs):
        time_flag = time.time()
        temp_result = func(*args,**kwargs)
        print("time cost:",time.time()-time_flag)
        return temp_result
    return wrap

@time_count
def loop_time(x,y):
        result=0
        for i in range(x,y):
            time.sleep(random.choice((0.1,0.2,0.3)))
            result=x+y
        return result

print(loop_time(1,10))