Python-列表的使用2

copy&循环&奇偶切片

copy(深/浅）

浅copy

names = ['a','b','c',['aaa','bbb','ccc'],'d','e','f']
names2 = names.copy() #copy变量names
print(names)
print(names2) #打印变量
names[1] = 'bb' #修改变量位置1的赋值
print(names)
print(names2)#打印变量，只有names变量有更改，names2变量不会更改
names[3][0]='aaaa'#修改变量内子变量位置0的赋值
print(names)
print(names2)#打印变量,names&nemes2变量都会调整，因为该变量是内存里直接改写的；　　

深copy

import copy #调用模块
names = ['a','b','c',['aaa','bbb','ccc'],'d','e','f']
names2 = copy.deepcopy(names) #深copy names变量
names[3][0]='aaaa'#修改变量内子变量位置0的赋值
print(names)
print(names2)#打印变量，names变量如何如何修改，names2都不会变换；

循环

names = ['a','b','c',['aaa','bbb','ccc'],'d','e','f']
for i in names: 
    print(i)

奇偶切片

names = ['a','b','c',['aaa','bbb','ccc'],'d','e','f']
print(names[0:-1:2])#取不到最后一个值
print(names[::2])#取得到最后一个值