列表内置方法
作用
定义
hobby=['paly','sleep']
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
hobby_list = ['play', 'swimming', 'dancing','666']
print(1, hobby_list[-1])
hobby_list[-1] = '233' # 索引修改
print(2, hobby_list[-1])
1 666 2 233
2.切片
hobby_list = ['play', 'swimming', 'dancing','666']
print(hobby_list[:])
print(hobby_list[::-1])# 从右到左
['play', 'swimming', 'dancing', '666']
['666', 'dancing', 'swimming', 'play']
3.长度
hobby_list = ['play', 'swimming', 'dancing','666']
print(len(hobby_list))
4
4.in/not in
hobby_list = ['play', 'swimming', 'dancing', '666']
print('play' in hobby_list) True
True
5.for 循环
for hobby in hobby_list:
print(hobby)
play swimming dancing 666
6.del 删除
del hobby_list[-1]
print(hobby_list)
play swimming dancing
7.append() 追加
hobby_list = ['play', 'swimming', 'dancing', '666']
hobby_list.append('dapao-->piao')
print(hobby_list)
['play', 'swimming', 'dancing', '666', 'dapao-->piao']
需要掌握
1.count () 计数
hobby_list = ['play', 'swimming', '666', 666, '666']
print(hobby_list.count('666')) #对列表内的某一个元素计数
2
2.extend() 扩展
hobby_list = ['play', 'swimming', '666', 666, '666']
hobby_list.extend([1,2])
print(hobby_list)
['play', 'swimming', '666', 666, '666', 1, 2]
3.clear() 清除
hobby_list.clear()
print(hobby_list)
[]
4.copy() 复制
hobby_list2 = hobby_list.copy() # 复制列表
5.pop() 删除（默认删除最后一个）
hobby_list = ['play', 'swimming', '666', 666, '666']
hobby_list.pop()
print(hobby_list)
['play', 'swimming', '666', 666]
6.index() 索引
print(hobby_list.index('play')) # 索引
print(hobby_list.index('play', 2, 4)) # 索引2-4内有没有该值
0 3
7.insert () 插入
hobby_list = ['play', 'swimming', '666', 666, '666']
hobby_list.insert(0, '1') # 插入
print(hobby_list)
['1', 'play', 'swimming', '666', 666, '666']
8.remove() 移除
hobby_list = ['play', 'swimming', '666', 666, '666']
hobby_list.remove('1') # 移除
print(hobby_list)
['play', '666', 666, '666']
9.reverse() 反转
hobby_list = ['play', 'swimming', '666', 666, '666']
hobby_list.reverse()
print(hobby_list)
['666', 666, '666', 'swimming', 'play']
10.sort（），使用sort列表的元素必须是同类型的
hobby_list = ['play', 'swimming', '666', '666']
hobby_list.sort()
print(hobby_list)
['666', '666', 'play', 'swimming']
存一个值or多个值：
多个值
有序or无序
有序
可变or不可变
