python_day06 匿名函数与内置函数 常用模块

匿名函数与内置函数

常用模块

1、匿名函数与内置函数

内置函数

内置函数
bool值为假的情况：None，空，0，False
print(abs(-1))   #取绝对值
all()所有可迭代对象内元素为真，结果为真。
print(all([1,2,'a',None]))    #False
print(all([]))                #True
any()有一个可迭代对象内元素为真，结果为真。
print(any([]))                #False
print(any([' ',None,False]))  #True
print(any(['',None,False]))   #False
print(any(['',None,False,1])) #True
bin,oct,hex 二/八/十进制
print(bin(10))
print(oct(10))
print(hex(10))
bytes字节
unicode----encode----->bytes
print('hello'.encode('utf-8'))
print(bytes('hello',encoding='utf-8'))
callable 判断是否可调用，可调用的目前学过的是函数。
print(callable(bytes))
print(callable(abs))
chr,ord ASCII编码表一一对应
print(chr(65))    #A
print(chr(90))    #Z
print(ord('#'))
内置函数，又被称为工厂函数
int
x=1 #x=int(1)
print(type(x))
x=int(2)
complex    #复数
float      #浮点型
str
list
tuple
dict
set #可变集合
frozenset #不可变集合
s={1,2,3,4} #s=set({1,2,3,4})
print(type(s))
s1=frozenset({1,2,3,4})
print(type(s1))
dir    #dir(sys) 列出sys可调用哪些属性
import sys
sys.path
sys.argv
print(dir(sys))
divmod 商和余数的小元组
print(divmod(10,3))   #（3,1）
print(divmod(102,20)) #（5,2）
enumerate
l=['a','b','c']
res=enumerate(l)  #迭代器
for i in res:
    print(i)
for index,item in enumerate(l):
    print(index,item)
globals,locals #查看全局作用域和局部作用域
print(globals())
hash   #hash函数
print(hash('abcdefg123'))
print(hash('abcdefg123'))
给函数加文档解释，用到单引号，双引号，三引号
def func():
    '''
    test function
    :return:
    '''
    pass
print(help(func))     #列出函数的注释信息
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
x=1
print(id(x))def func():passprint(id(func))print(func)isinstancex=1print(type(x) is int)print(isinstance(x,int))  #判断x是不是int实例x=int(1)迭代器iternextlenmaxprint(max([1,2,3,10]))print(max(['a','b']))print(min([1,2,3,10]))powprint(pow(3,2,2)) #3**2%2rangerepr，strprint(type(str(1)))print(type(repr(1))) #==str 转换为strreversedl=[1,'a',2,'c']print(list(reversed(l)))print(l)slice  #切割l=[1,2,3,4,5,6]print(l[0:4:2])s=slice(0,4,2)print(l[s])sorted #排序l=[1,10,4,3,-1]print(sorted(l,reverse=True))sumprint(sum([1, 2,3]))print(sum(i for i in range(10)))varsimport m1print(vars(m1) == m1.__dict__)zip:拉链s='hellosssssssssssssssss'l=[1,2,3,4,5]print(list(zip(s,l)))__import__     #需求来自于用户交互字符串方式导入模块import sysm_name=input('module>>: ')if m_name == 'sys':    m=__import__(m_name)    print(m)    print(m.path)sys=__import__('sys')print(sys)round #留小数点print(round(3.565,2)) #3.56print(round(3.555,2)) #3.56filter,map,reduce 重点面向对象objectsuper__dict__isinstanceissubclassclassmethodstaticmethodpropertydelattrhasattrsetattrgetattr了解compileevalexec

匿名函数

def func(x,y,z=1):
    return x+y+z
print(func)
print(func(1,2,3))
匿名函数:1. 没有名字 2：函数体自带return
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))
匿名函数与变量关系类似
x=1
1
print(x)
print(1)
匿名函数的应用场景：
应用于一次性的场景，临时使用

匿名函数
lambda x,y,z=1:x+y+z   #省略了return
特点：1、没有名字。2、函数体自带return
应用场景：应用于一次性的场景，临时使用。
与匿名函数结合使用
max,min,sorted
获得薪资最高的人名
salaries={
'egon':3000,
'alex':100000000,
'wupeiqi':10000,
'yuanhao':2000
}
print(max(salaries))    #yuanhao    按照字母排列顺序列出
print(max(salaries.values()))   #100000000 得到结果为数字
验证print(max(salaries))的字母排序结果
t1=(1,'h',3,4,5,6)
t2=(1,'y',3)
print(t1 > t2)
t1=(10000000,'alex')
t2=(3000,'egon')
print(t1 > t2)
使用拉链函数可得到最高工资人员
print(max(zip(salaries.values(),salaries.keys()))[1])
使用max的key关键字可得到最高工资人员
def get_value(name):
    return salaries[name]
print(max(salaries,key=get_value))
l=[]
for name in salaries:
    res=get_value(name)
    l.append(res)
print(max(l))
使用max的key关键字可得到最高工资人员
key关键字使用lambda函数
lambda name:salaries[name]
print(max(salaries,key=lambda name:salaries[name]))
print(min(salaries,key=lambda name:salaries[name]))
salaries={
'egon':3000,
'alex':100000000,
'wupeiqi':10000,
'yuanhao':2000
}
def get_value(name):
    return salaries[name]
print(sorted(salaries))
print(sorted(salaries,key=get_value))
print(sorted(salaries,key=get_value,reverse=True))



filter,map,reduce
names=['alex','wupeiqi','yuanhao','yanglei','egon']


res=map(lambda x:x if x == 'egon' else x+'SB',names)
print(res)
print(list(res))


def my_map(func,seq):
    for item in seq:
        yield func(item)

res1=my_map(lambda x:x+'_SB',names)
print(next(res1))
print(next(res1))
print(next(res1))


from functools import reduce
print(reduce(lambda x,y:x+y,range(101),100))
print(reduce(lambda x,y:x+y,range(101)))

l=[1,2,'a','b',3,'c','d']
filter函数
names=['alex_SB','wupeiqi_SB','yuanhao_SB','yanglei_SB','egon']
print(list(filter(lambda name:name.endswith('SB'),names)))

匿名函数lambda及其应用

cmd='print(x)'
x=1
eval(cmd,{'x':0},{'x':10000000})
eval(cmd,{'x':0},{'y':10000000})
s='for i in range(10):print(i,x)'
code=compile(s,'','exec')
print(code)
exec(code,{},{'x':1111})

常用模块

正则模块：

import re
print(re.findall('w','hello_ | egon 123'))
print(re.findall('W','hello_ | egon 123'))
print(re.findall('s','hello_ | egon 123 
 	'))
print(re.findall('S','hello_ | egon 123 
 	'))
print(re.findall('d','hello_ | egon 123 
 	'))
print(re.findall('D','hello_ | egon 123 
 	'))
print(re.findall('h','hello_ | hello h egon 123 
 	'))
# print(re.findall('Ahe','hello_ | hello h egon 123 
 	'))
print(re.findall('^he','hello_ | hello h egon 123 
 	'))
# print(re.findall('123','hello_ | hello h egon 123 
 	123'))
print(re.findall('123$','hello_ | hello h egon 123 
 	123'))
print(re.findall('
','hello_ | hello h egon 123 
 	123'))
print(re.findall('	','hello_ | hello h egon 123 
 	123'))
. [] [^]
.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'))
                    a.c
print(re.findall('a.c','a a1c a*c a2c abc a
c',re.DOTALL))
print(re.findall('a.c','a a1c a*c a2c abc a
c',re.S))
[]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
c',re.S))
print(re.findall('a[a-zA-Z]c','aac abc aAc a12c a1c a*c a2c a c a
c',re.S))
print(re.findall('a[^a-zA-Z]c','aac abc aAc a12c a1c a*c a2c a c a
c',re.S))
print(re.findall('a[+/*-]c','a-c a+c a/c aac abc aAc a12c a1c a*c a2c a c a
c',re.S))
:转义
print(re.findall(r'a\c','ac abc')) #rawstring

? * + {}：左边有几个字符，如果有的话，贪婪匹配
?左边那一个字符有0个或者1个
print(re.findall('ab?','aab a ab aaaa'))
                       ab?
*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'))
.* .*?
.*贪婪匹配
print(re.findall('a.*c','a123c456c'))
.*?非贪婪匹配
print(re.findall('a.*?c','a123c456c'))
|
print(re.findall('company|companies','Too many companies have gone bankrupt, and the next one is my company'))
                                                                                                company|companies
print(re.findall('compan|companies','Too many companies have gone bankrupt, and the next one is my company'))
():分组
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'))
re的其他方法
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.search('^ab','123ab456'))
print(re.split('b','abcde'))
print(re.split('[ab]','abcde'))
print(re.sub('alex','SB','alex make love alex alex',1))
print(re.subn('alex','SB','alex make love alex alex',1))
print(re.sub('(w+)(W+)(w+)(W+)(w+)',r'52341','alex make love'))
print(re.sub('(w+)( .* )(w+)',r'321','alex make love'))
obj=re.compile('d{2}')
print(obj.search('abc123eeee').group()) #12
print(obj.findall('abc123eeee')) #12

print(re.findall('-?d+.?d+',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+.?d*',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+.d+',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+.d+|(-?d+)',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+.d+|-?d+',"1-12*(60+(-40.35/5)-(-4*3))"))
print(re.findall('-?d+|-?d+.d+',"1-12*(60+(-40.35/5)-(-4*3))"))

时间模块

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()))

random模块
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)
产生随机验证码
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)
os模块
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:acda.txt'))
print(os.path.basename(r'C:acda.txt'))
print(os.path.split(r'C:acda.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)
sys模块
import sys,time
for i in range(1,100):
    sys.stdout.write('
%s' %('#'*i))
    sys.stdout.flush()
    time.sleep(0.5)
for i in range(1,100):
    print('
%s' %('#'*i),file=sys.stdout,flush=True,end='')
    time.sleep(0.01)
#进度条：
print('<%s>' %'hello')
print('<%-10s>' %'hello')
print('<%-10s>' %'helloe')
print('<%-10s>' %'helloee')
print('<%-10s>' %'#')
print('<%-10s>' %'##')
print('<%-10s>' %'###')
print('<%-10s>' %'####')
print('<%-10s>' %'#####')
print('<%-10s>' %'helloee')
width=20
print('<%%-%ds>' %width) #<%-10s>
print(('<%%-%ds>' %width) %('hello'))
<%-10s> %('hello')
width=20
print(('[%%-%ds]' %width) %('#'))
print(('[%%-%ds]' %width) %('##'))
print(('[%%-%ds]' %width) %('###'))
def progress(percent,width=50): #51
    if percent >= 100:
        # print('
[%s] 100%%' %(width*'#'))
        percent=100
    show_str=('[%%-%ds]' %width) %(int(width*percent/100)*'#')
    print('
%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)
json序列化
import json
dic={'name':'egon','age':18}
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':'egon','age':18}
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)
pikcle序列化
import pickle
dic={'name':'egon','age':18}
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':'egon','age':18}
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'))
pikcle反序列化
import pickle
def func():
    print('反序列化的文件')
pickle.dump(func,open('func.pkl','wb'))
f=pickle.load(open('func.pkl','rb'))
print(f)
class Foo:
    pass
obj1=Foo()
obj2=Foo()
print(obj1 is obj2)
pickle.dump(obj1,open('class.pkl','wb'))
import pickle
pickle.load(open('class.pkl','rb'))
l1=list()
l2=list()
print(type(l1))
print(type(l2))
shevel模块
import shelve
f=shelve.open(r'sheve.shl')
f['alex']={'age':28,'pwd':'alex3714'}
f['egon']={'age':18,'pwd':'3714'}
f.close()
反序列化
import shelve
obj=shelve.open(r'sheve.shl')
print(obj['alex'])
print(obj['egon'])
obj.close()
for i in obj:
    print(i,obj[i])