一、for循环
# msg=‘hello‘
# msg=[1,2,3,4,5,6]
msg=(1,2,3,4,5,6)
msg_dic={
‘apple‘:10,
‘tesla‘:1000000,
‘mac‘:3000,
‘lenovo‘:30000,
‘chicken‘:10,
}
# index=0
# while index < len(msg):
# print(msg[index])
# index+=1
# msg=‘hello‘
# # msg=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘]
# # msg=(‘a‘,‘b‘,‘c‘,‘d‘,‘e‘)
# for i in range(len(msg)):
# print(i,msg[i])
#不依赖索引的取值
# for item in msg_dic:
# print(item,msg_dic[item])
# msg=‘hello‘
# msg=[1,2,3,4,5,6]
# msg=(1,2,3,4,5,6)
# for item in msg:
# print(item)
#补充
#range:顾头不顾尾，默认从0开始
# print(type(range(1,2)))
# for i in range(10):
# print(i,type(i))
# for i in range(1,10,2):
# print(i,type(i))
# for i in range(10,1,-2):
# print(i)
# for i in range(1,10,1):
# print(i)
# for i in range(9,0,-1):
# print(i)
#break
#continue
# for i in range(10):
# if i == 4:
# # break
# continue
# print(i)
#for+else
# for i in range(10):
# print(i)
# break
# else:
# print(‘===>‘)
二、python赋值补充:
x=10
#链式赋值
# a=b=c=d=e=f=10
# print(a,b,c,d,e,f)
#增量赋值
x=10
y=‘a‘
# temp=x
# x=y
# y=temp
# print(x,y)
# x,y=y,x
# print(x,y)
#值的解压
msg=‘hello‘
l=[1,2,3]
# a,b,c,d,e=msg
# print(a,b,c,d,e)
# a,_,_,_,e=msg
# a,*_,e=msg
# print(a)
# print(e)
# dic={‘a‘:1,‘b‘:2,‘c‘:3}
# x,y,z=dic
# print(x,y,z)
三、列表
# l=[1,2,3] #l=list([1,2,3]) # print(type(l)) #pat1===》优先掌握部分 # 索引 # # 切片 l=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘] # print(l[1:5]) # print(l[1:5:2]) # print(l[2:5]) # print(l[-1]) #了解 # print(l[-1:-4]) # print(l[-4:]) # l=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘] # print(l[-2:]) # 追加 # hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘] # hobbies.append(‘girls‘) # print(hobbies) # 删除 hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘] # x=hobbies.pop(1) #不是单纯的删除，是删除并且把删除的元素返回，我们可以用一个变量名去接收该返回值 # print(x) # print(hobbies) # x=hobbies.pop(0) # print(x) # # x=hobbies.pop(0) # print(x) #队列：先进先出 queue_l=[] #入队 # queue_l.append(‘first‘) # queue_l.append(‘second‘) # queue_l.append(‘third‘) # print(queue_l) #出队 # print(queue_l.pop(0)) # print(queue_l.pop(0)) # print(queue_l.pop(0)) #堆栈:先进后出，后进先出 # l=[] # #入栈 # l.append(‘first‘) # l.append(‘second‘) # l.append(‘third‘) # #出栈 # print(l) # print(l.pop()) # print(l.pop()) # print(l.pop()) #了解 # del hobbies[1] #单纯的删除 # hobbies.remove(‘eat‘) #单纯的删除，并且是指定元素去删除 # 长度 # hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘] # print(len(hobbies)) # 包含in # hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘] # print(‘sleep‘ in hobbies) # msg=‘hello world egon‘ # print(‘egon‘ in msg) ##pat2===》掌握部分 hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘] # hobbies.insert(1,‘walk‘) # hobbies.insert(1,[‘walk1‘,‘walk2‘,‘walk3‘]) # print(hobbies) # print(hobbies.count(‘eat‘)) # print(hobbies) # hobbies.extend([‘walk1‘,‘walk2‘,‘walk3‘]) # print(hobbies) hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘] # print(hobbies.index(‘eat‘)) #pat3===》了解部分 hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘] # hobbies.clear() # print(hobbies) # l=hobbies.copy() # print(l) # l=[1,2,3,4,5] # l.reverse() # print(l) l=[100,9,-2,11,32] l.sort(reverse=True) print(l)
四、元组
#为何要有元组，存放多个值，元组不可变，更多的是用来做查询
t=(1,[1,3],‘sss‘,(1,2)) #t=tuple((1,[1,3],‘sss‘,(1,2)))
# print(type(t))
# #元组可以作为字典的key
# d={(1,2,3):‘egon‘}
# print(d,type(d),d[(1,2,3)])
# 索引
#
# 切片
# goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)
# print(goods[1:3])
#
# 长度
#
#in:
#字符串:子字符串
#列表：元素
#元组：元素
#字典：key
# goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)
# print(‘iphone‘ in goods)
# d={‘a‘:1,‘b‘:2,‘c‘:3}
# print(‘b‘ in d)
#掌握
# goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)
# print(goods.index(‘iphone‘))
# print(goods.count(‘iphone‘))
#补充：元组本身是不可变的，但是内部的元素可以是可变类型
t=(1,[‘a‘,‘b‘],‘sss‘,(1,2)) #t=tuple((1,[1,3],‘sss‘,(1,2)))
# t[1][0]=‘A‘
# print(t)
# t[1]=‘aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa‘
五、字典
info=[‘egon‘,‘male‘,18,180,75]
info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# 常用操作：
#
# 存/取
info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# print(info_dic[‘name11111111‘])
# print(info_dic.get(‘name‘,None))
#pop：key存在则弹出值，不存在则返回默认值，如果没有默认值则报错
# print(info_dic.pop(‘nam123123123123123123e‘,None))
# print(info_dic)
# print(info_dic.popitem())
# print(info_dic)
# info_dic[‘level‘]=10
# print(info_dic)
#
# 删除
info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# info_dic.pop()
# info_dic.popitem()
# del info_dic[‘name‘]
#
# 键s，值s，键值对
info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# print(info_dic.keys())
# print(info_dic.values())
# print(info_dic.items())
# for k in info_dic:
# # print(k,info_dic[k])
# print(k)
# print(‘========>‘)
# for k in info_dic.keys():
# print(k)
# for val in info_dic.values():
# print(val)
# for k,v in info_dic.items(): #k,v=(‘name‘, ‘egon‘)
# print(k,v)
# 长度
# info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# print(len(info_dic))
#
# 循环
#
# 包含in
# info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# print(‘name‘ in info_dic)
# print(‘name‘ in info_dic.keys())
# print(‘egon‘ in info_dic.values())
# print((‘name‘,‘egon‘) in info_dic.items())
#掌握
info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# info_dic.update({‘a‘:1,‘name‘:‘Egon‘})
# print(info_dic)
# info_dic[‘hobbies‘]=[]
# info_dic[‘hobbies‘].append(‘study‘)
# info_dic[‘hobbies‘].append(‘read‘)
# print(info_dic)
#setdefault:key不存在则设置默认值，并且放回值默认值
#key存在则不设置默认，并且返回已经有的值
# info_dic.setdefault(‘hobbies‘,[1,2])
# print(info_dic)
# info_dic.setdefault(‘hobbies‘,[1,2,3,4,5])
# print(info_dic)
# info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}
# {‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘]}
# info_dic.setdefault(‘hobbies‘,[]).append(‘study‘)
# {‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘,‘read‘]}
# info_dic.setdefault(‘hobbies‘,[]).append(‘read‘)
# {‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘,‘read‘,‘sleep‘]}
# info_dic.setdefault(‘hobbies‘,[]).append(‘sleep‘)
# l=info_dic.setdefault(‘hobbies‘,[])
# print(l,id(l))
# print(id(info_dic[‘hobbies‘]))
# print(info_dic)
#了解
# d=info_dic.copy()
# print(d)
# info_dic.clear()
# print(info_dic)
# d=info_dic.fromkeys((‘name‘,‘age‘,‘sex‘),None)
# print(d)
# d1=dict.fromkeys((‘name‘,‘age‘,‘sex‘),None)
# d2=dict.fromkeys((‘name‘,‘age‘,‘sex‘),(‘egon‘,18,‘male‘))
# print(d1)
# print(d2)
# info=dict(name=‘egon‘,age=18,sex=‘male‘)
# print(info)
#
# info=dict([(‘name‘,‘egon‘),(‘age‘,18)])
# print(info)
时间： 2024-10-12 05:58:41