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第六篇：python基础_6 内置函数与常用模块（一）

时间：2017-08-09 12:51:51      阅读：187      评论：0      收藏：0      [点我收藏+]

标签：oms   recv   hex   for   .sh   解释   help   glob   功能   

本篇内容

  1. 内置函数
  2. 匿名函数
  3. re模块
  4. time模块
  5. random模块
  6. os模块
  7. sys模块
  8. json与pickle模块
  9. shelve模块

 

一、 内置函数

1.定义

内置函数又被称为工厂函数。

技术分享

2.常用的内置函数

（1）abs()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(abs(-1))

 （2）all()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(all([1,2,‘a‘,None]))
print(all([]))

 （3）any()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(any([]))
print(any([‘ ‘,None,False]))
print(any([‘‘,None,False]))
print(any([‘‘,None,False,1]))

 （4）bin(),oct(),hex()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(bin(10))
print(oct(10))
print(hex(10))

 （5）bytes()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

#unicode----encode----->bytes
print(‘hello‘.encode(‘utf-8‘))
print(bytes(‘hello‘,encoding=‘utf-8‘))

 （6）callable()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(callable(bytes))
print(callable(abs))

 （7）chr(),ord()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(chr(65))
print(chr(90))
print(ord(‘#‘))

 （8）int()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

x=1
print(type(x))
x=int(2)
print(type(x))

 complex()、float()、str()、list()、tuple()、dict()与int()同理

（9）set()，可变集合

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

s={1,2,3,4}
print(type(s))

 （10）frozenset()，不可变集合

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

s1=frozenset({1,2,3,4})
print(type(s1))

 （11）dir()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import sys
#sys.path
# sys.argv
print(dir(sys))

 （12）divmod()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(divmod(10,3))
print(divmod(102,20))

 （13）enumerate()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

l=[‘a‘,‘b‘,‘c‘]
res=enumerate(l)
for i in res:
    print(i)
for index,item in enumerate(l):
    print(index,item)

 （14）globals(),locals()，查看全局作用域和局部作用域

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(globals())

 （15）hash()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(hash(‘abcdefg123‘))
print(hash(‘abcdefg123‘))

 （16）help()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

def func():
    ‘‘‘
    test function
    :return:
    ‘‘‘
    pass

print(help(func))

 （17）id()，是python解释器实现的功能，只是反映了变量在内存的地址，但并不是真实的内存地址

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

x=1
print(id(x))
def func():
    pass
print(id(func))
print(func)

（18）isinstance()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

x=1
print(type(x) is int)
print(isinstance(x,int))

 （19）max(),min()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(max([1,2,3,10]))
print(max([‘a‘,‘b‘]))
print(min([1,2,3,10]))

 （20）pow()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(pow(3,2,2)) #3**2%2

 （21）repr(),str()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(type(str(1)))
print(type(repr(1)))

 （22）reversed()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

l=[1,‘a‘,2,‘c‘]
print(list(reversed(l)))
print(l)

 （23）slice()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

l=[1,2,3,4,5,6]
print(l[0:4:2])

s=slice(0,4,2)
print(l[s])

 （24）sorted()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

l=[1,10,4,3,-1]
print(sorted(l,reverse=True))

 （25）sum()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(sum([1, 2,3]))
print(sum(i for i in range(10)))

 （26）vars()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import m1
print(vars(m1) == m1.__dict__)

 （27）zip()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

s=‘helloss‘
l=[1,2,3,4,5]
print(list(zip(s,l)))

 （28）__import__()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import sys

m_name=input(‘module>>: ‘)
if m_name == ‘sys‘:
    m=__import__(m_name)
    print(m)
    print(m.path)

sys=__import__(‘sys‘)
print(sys)

 （29）round()

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

print(round(3.565,2))
print(round(3.555,2))

 

二、 匿名函数

1.定义

 匿名函数：

（1）没有名字。

（2）函数体自带return。

匿名函数的应用场景：
应用于一次性的场景，临时使用。

2.使用

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

def func(x,y,z=1):
    return x+y+z

print(func)
print(func(1,2,3))

print(lambda x,y,z=1:x+y+z)
f=lambda x,y,z=1:x+y+z
print(f)
print(f(1,2,3))

 

三、 re模块

技术分享

（1）

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

print(re.findall(‘\w‘,‘hello_ | yanglei 123‘))
print(re.findall(‘\W‘,‘hello_ | yanglei 123‘))
print(re.findall(‘\s‘,‘hello_ | yanglei 123 \n \t‘))
print(re.findall(‘\S‘,‘hello_ | yanglei 123 \n \t‘))
print(re.findall(‘\d‘,‘hello_ | yanglei 123 \n \t‘))
print(re.findall(‘\D‘,‘hello_ | yanglei 123 \n \t‘))
print(re.findall(‘h‘,‘hello_ | hello h yanglei 123 \n \t‘))
print(re.findall(‘\Ahe‘,‘hello_ | hello h yanglei 123 \n \t‘))
print(re.findall(‘^he‘,‘hello_ | hello h yanglei 123 \n \t‘))
print(re.findall(‘123\Z‘,‘hello_ | hello h yanglei 123 \n \t123‘))
print(re.findall(‘123$‘,‘hello_ | hello h yanglei 123 \n \t123‘))
print(re.findall(‘\n‘,‘hello_ | hello h yanglei 123 \n \t123‘))
print(re.findall(‘\t‘,‘hello_ | hello h yanglei 123 \n \t123‘))

 （2）. [] [^]

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

#.本身代表任意一个字符
print(re.findall(‘a.c‘,‘a a1c a*c a2c abc a c aaaaaac aacc‘))

#[]内部可以有多个字符，但是本身只配多个字符中的一个
print(re.findall(‘a[0-9][0-9]c‘,‘a a12c a1c a*c a2c a c a\nc‘,re.S))
print(re.findall(‘a[a-zA-Z]c‘,‘aac abc aAc a12c a1c a*c a2c a c a\nc‘,re.S))
print(re.findall(‘a[^a-zA-Z]c‘,‘aac abc aAc a12c a1c a*c a2c a c a\nc‘,re.S))
print(re.findall(‘a[\+\/\*\-]c‘,‘a-c a+c a/c aac abc aAc a12c a1c a*c a2c a c a\nc‘,re.S))

 （3）\：转义

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

print(re.findall(r‘a\\c‘,‘a\c abc‘))

 （4）? * + {}：左边有几个字符，如果有的话，贪婪匹配

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

#?左边那一个字符有0个或者1个
print(re.findall(‘ab?‘,‘aab a ab aaaa‘))

#*左边那一个字符有0个或者无穷个
print(re.findall(‘ab*‘,‘a ab abb abbb abbbb bbbbbb‘))
print(re.findall(‘ab{0,}‘,‘a ab abb abbb abbbb bbbbbb‘))

#+左边那一个字符有1个或者无穷个
print(re.findall(‘ab+‘,‘a ab abb abbb abbbb bbbbbb‘))
print(re.findall(‘ab{1,}‘,‘a ab abb abbb abbbb bbbbbb‘))

#{n,m}左边的字符有n-m次
print(re.findall(‘ab{3}‘,‘a ab abb abbb abbbb bbbbbb‘))
print(re.findall(‘ab{2,3}‘,‘a ab abb abbb abbbb bbbbbb‘))

 （5）.* .*?

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

#.*贪婪匹配
print(re.findall(‘a.*c‘,‘a123c456c‘))

#.*?非贪婪匹配
print(re.findall(‘a.*?c‘,‘a123c456c‘))

 （6）|

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

print(re.findall(‘company|companies‘,‘Too many companies have gone bankrupt, and the next one is my company‘))
print(re.findall(‘compan|companies‘,‘Too many companies have gone bankrupt, and the next one is my company‘))

 （7）()：分组

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

print(re.findall(‘ab+‘,‘abababab123‘))
print(re.findall(‘ab+123‘,‘abababab123‘))

print(re.findall(‘ab‘,‘abababab123‘))
print(re.findall(‘(ab)‘,‘abababab123‘))
print(re.findall(‘(a)b‘,‘abababab123‘))
print(re.findall(‘a(b)‘,‘abababab123‘))
print(re.findall(‘(ab)+‘,‘abababab123‘))
print(re.findall(‘(?:ab)+‘,‘abababab123‘))

print(re.findall(‘(ab)+123‘,‘abababab123‘))
print(re.findall(‘(?:ab)+123‘,‘abababab123‘))
print(re.findall(‘(ab)+(123)‘,‘abababab123‘))

print(re.findall(‘compan(y|ies)‘,‘Too many companies have gone bankrupt, and the next one is my company‘))
print(re.findall(‘compan(?:y|ies)‘,‘Too many companies have gone bankrupt, and the next one is my company‘))

 （8）re的其他方法

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import re

print(re.findall(‘ab‘,‘abababab123‘))
print(re.search(‘ab‘,‘abababab123‘).group())
print(re.search(‘ab‘,‘12aasssdddssssssss3‘))
print(re.search(‘ab‘,‘12aasssdddsssssssab3sssssss‘).group())
print(re.search(‘ab‘,‘123ab456‘))

print(re.match(‘ab‘,‘123ab456‘))

print(re.split(‘b‘,‘abcde‘))
print(re.split(‘[ab]‘,‘abcde‘))

print(re.sub(‘xiaolan‘,‘xiaohong‘,‘xiaolan make love xiaolan xiaolan‘,1))
print(re.subn(‘xiaolan‘,‘xiaohong‘,‘xiaolan make love xiaolan xiaolan‘,1))
print(re.sub(‘(\w+)(\W+)(\w+)(\W+)(\w+)‘,r‘\5\2\3\4\1‘,‘Toms make love‘))
print(re.sub(‘(\w+)( .* )(\w+)‘,r‘\3\2\1‘,‘Toms make love‘))

obj=re.compile(‘\d{2}‘)
print(obj.search(‘abc123eeee‘).group())
print(obj.findall(‘abc123eeee‘))

 

四、time模块

模块方法

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import time

print(time.time())
print(time.strftime(‘%Y-%m-%d %X‘))

print(time.localtime())
print(time.gmtime()) #UTC
print(time.localtime().tm_mon)

print(time.localtime(123123123))
print(time.gmtime(123123123))

print(time.mktime(time.localtime()))

print(time.strftime(‘%Y‘,time.gmtime()))

‘2017-03-01‘
print(time.strptime(‘2017-03-01‘,‘%Y-%m-%d‘))

print(time.ctime(12312312))
print(time.asctime(time.gmtime()))

 

五、random模块

1.模块方法

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import random
print(random.sample([1,‘23‘,[4,5]],2))

print(random.uniform(1,3))

item=[1,3,5,7,9]
random.shuffle(item)
print(item)

2. 生成秘钥应用

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import random
def make_code(n):
    res=‘‘
    for i in range(n):
        s1=str(random.randint(0,9))
        s2=chr(random.randint(65,90))
        res+=random.choice([s1,s2])
    return res
print(make_code(10))

 

六、os模块

模块方法

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import os

print(os.listdir(‘.‘))

print(os.stat(‘m1.py‘).st_size)

print(os.sep)
print(os.linesep)
print(os.pathsep)

print([os.sep,os.linesep,os.pathsep])

res=os.system(‘dir .‘)
print(‘====?>‘,res)

print(os.path.dirname(r‘C:\a\b\c\d\a.txt‘))
print(os.path.basename(r‘C:\a\b\c\d\a.txt‘))
print(os.path.split(r‘C:\a\b\c\d\a.txt‘))

print(os.stat(‘m1.py‘).st_atime)
print(os.stat(‘m1.py‘).st_size)
print(os.path.getsize(‘m1.py‘))

print(os.path.join(‘C:\\‘,‘a‘,‘b‘,‘c‘,‘d.txt‘))
print(os.path.join(‘C:\\‘,‘a‘,‘b‘,‘D:\\‘,‘c‘,‘d.txt‘))

print(os.path.normcase(‘c:/wiNdows\\system32\\‘)  )

print(os.path.normpath(‘c://wIndows\\System32\\../Temp/‘)  )

a=‘/Users/jieli/test1/\\\a1/\\\\aa.py/../..‘
print(os.path.normpath(a))


print(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

BASE_DIR=os.path.normpath(os.path.join(
    os.path.abspath(__file__),
    ‘..‘,
    ‘..‘
)
)
print(BASE_DIR)

 

七、sys模块

模拟进度条应用

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import sys,time


def progress(percent,width=50): #51
    if percent >= 100:
        # print(‘\r[%s] 100%%‘ %(width*‘#‘))
        percent=100
    show_str=(‘[%%-%ds]‘ %width) %(int(width*percent/100)*‘#‘)
    print(‘\r%s %d%%‘ %(show_str,percent),file=sys.stdout,flush=True,end=‘‘)
#
total_size=1025121
recv_size=0

while recv_size < total_size:
    time.sleep(0.01) #模拟下载的网络延迟
    recv_size+=1024
    recv_per=int(100*recv_size/total_size)
    progress(recv_per,width=10)

 

八、json与pickle模块

（1）json

应用平台广泛

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import json
dic={‘name‘:‘yanglei‘,‘age‘:23}

print(type(json.dumps(dic)))

with open(‘a.json‘,‘w‘) as f:
    f.write(json.dumps(dic))

with open(‘a.json‘,‘r‘) as f:
    data=f.read()
    dic=json.loads(data)
    print(dic[‘name‘])

dic={‘name‘:‘yanglei‘,‘age‘:23}
json.dump(dic,open(‘b.json‘,‘w‘))
print(json.load(open(‘b.json‘,‘r‘))[‘name‘])

with open(‘c.json‘,‘r‘) as f:
    data=f.read()
    #[null,true,false,1]
    eval(data)

 （2）pickle

只对python有效

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import pickle

dic={‘name‘:‘yanglei‘,‘age‘:23}

print(pickle.dumps(dic))
with open(‘d.pkl‘,‘wb‘) as f:
    f.write(pickle.dumps(dic))

with open(‘d.pkl‘,‘rb‘) as f:
    dic=pickle.loads(f.read())
    print(dic[‘name‘])

dic={‘name‘:‘yanglei‘,‘age‘:23}
pickle.dump(dic,open(‘e.pkl‘,‘wb‘))

print(pickle.load(open(‘e.pkl‘,‘rb‘))[‘name‘])

def func():
    print(‘from func‘)

import json
print(json.dumps(func))

import pickle
print(pickle.dumps(func))
pickle.dump(func,open(‘func.pkl‘,‘wb‘))

 

九、shelve模块

 模块方法

#!/usr/binl/env python
#encoding: utf-8
#author: YangLei

import shelve

f=shelve.open(r‘sheve.shl‘)

f[‘yanglei‘]={‘age‘:23,‘pwd‘:‘123456‘}
f[‘xiaolan‘]={‘age‘:18,‘pwd‘:‘123456‘}
f.close()

obj=shelve.open(r‘sheve.shl‘)

print(obj[‘yanglei‘])
print(obj[‘xiaolan‘])

obj.close()

for i in obj:
    print(i,obj[i])

 

第六篇：python基础_6 内置函数与常用模块（一）

标签：oms   recv   hex   for   .sh   解释   help   glob   功能   

原文地址：http://www.cnblogs.com/00doudou00/p/7323556.html
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