列表类型内置方法 - 好文

list(掌握)

1.用途：多个装备、多个爱好、多门课程，甚至是多个女朋友

2.定义：[]内可以有多个任意类型的值，逗号分隔元素
# my_girl_friend = list(['jason','tank','sean']) my_girl_friend = ['jason',
'tank', 'sean'] print(f"my_girl_friend: {my_girl_friend}") my_girl_friend:
['jason', 'tank', 'sean'] l = list('hello nick') print(f"l: {l}") l: ['h', 'e',
'l', 'l', 'o', ' ', 'n', 'i', 'c', 'k']
3.常用操作+内置方法：常用操作和内置方法分为优先掌握（今天必须得记住）、需要掌握（一周内记住）、其他操作（了解）三个部分。

优先掌握(*****)

1.按索引取值（正向取值+反向取值），即可存也可以取
# list之索引取值 name_list = ['nick', 'jason', 'tank', 'sean'] name_list[0] = 'nick
handsom' # name_list[1000] = 'tank sb' # 报错 print(f"name_list[0]:
{name_list[0]}") name_list[0]: nick handsom
2.切片
# list之切片 name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list[0:3:2]: {name_list[0:3:2]}") name_list[0:3:2]: ['nick',
'tank']
3.长度
# list之长度 name_list = ['nick', 'jason', 'tank', 'sean']
print(f"len(name_list): {len(name_list)}") len(name_list): 4
4.成员运算in和not in
# list之成员运算in和not in name_list = ['nick', 'jason', 'tank', 'sean']
print(f"'tank sb' in name_list: {'tank sb' in name_list}") print(f"'nick
handsome' not in name_list: {'nick handsome' not in name_list}") 'tank sb' in
name_list: False 'nick handsome' not in name_list: True
5.追加值
# list之追加值 name_list = ['nick', 'jason', 'tank', 'sean']
name_list.append('tank sb') print(f"name_list: {name_list}") name_list:
['nick', 'jason', 'tank', 'sean', 'tank sb']
6.删除
# list之删除 name_list = ['nick', 'jason', 'tank', 'sean'] del name_list[2]
print(f"name_list: {name_list}") name_list: ['nick', 'jason', 'sean']
7.循环
# list之循环 name_list = ['nick', 'jason', 'tank', 'sean'] for name in name_list:
print(name) nick jason tank sean
需要掌握(****)

1.insert()
# list之insert() name_list = ['nick', 'jason', 'tank', 'sean']
name_list.insert(1, 'handsome') print(f"name_list: {name_list}") name_list:
['nick', 'handsome', 'jason', 'tank', 'sean']
2.pop()
# list之pop()，pop()默认删除最后一个元素 name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list.pop(1): {name_list.pop(1)}") print(f"name_list: {name_list}")
name_list.pop(1): jason name_list: ['nick', 'tank', 'sean']
3.remove()
# list之remove() name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list.remove('nick'): {name_list.remove('nick')}")
print(f"name_list: {name_list}") name_list.remove('nick'): None name_list:
['jason', 'tank', 'sean']
4.count()
# list之count() name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list.count('nick'): {name_list.count('nick')}")
name_list.count('nick'): 1
5.index()
# list之index() name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list.index('nick'): {name_list.index('nick')}")
name_list.index('nick'): 0
6.clear()
# list之clear() name_list = ['nick', 'jason', 'tank', 'sean'] name_list.clear()
print(f"name_list: {name_list}") name_list: []
7.copy()
# list之copy() name_list = ['nick', 'jason', 'tank', 'sean']
print(f"name_list.copy(): {name_list.copy()}") name_list.copy(): ['nick',
'jason', 'tank', 'sean']
8.extend()
# list之extend() name_list = ['nick', 'jason', 'tank', 'sean'] name_list2 =
['nick handsome'] name_list.extend(name_list2) print(f"name_list: {name_list}")
name_list: ['nick', 'jason', 'tank', 'sean', 'nick handsome']
9.reverse()
# list之reverse() name_list = ['nick', 'jason', 'tank', 'sean']
name_list.reverse() print(f"name_list: {name_list}") name_list: ['sean',
'tank', 'jason', 'nick']
10.sort()
# list之sort()，使用sort列表的元素必须是同类型的 name_list = ['nick', 'jason', 'tank', 'sean']
name_list.sort() print(f"name_list: {name_list}") name_list.sort(reverse=True)
print(f"name_list_reverse: {name_list}") name_list: ['jason', 'nick', 'sean',
'tank'] name_list_reverse: ['tank', 'sean', 'nick', 'jason']

4.存一个值or多个值：多个值

5.有序or无序：有序
hobby_list = ['read', 'run', 'girl'] print(f'first:{id(hobby_list)}')
hobby_list[2] = '' print(f'second:{id(hobby_list)}') first:4522187016
second:4522187016
6.可变or不可变：可变数据类型

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