列表类型的内置方法
- 1.用途
存多个数据
2.定义
[]内可以有多个任意数据类型的元素，用逗号分隔
hobby_list=['read','run','sleep']
l=list('hello')
print(l) #['h', 'e', 'l', 'l', 'o']
- 3.常用操作和内置方法
1.按索引取值，索引不存在会报错
name_list = ['nick', 'jason', 'tank', 'sean']
name_list[0] = 'nick handsom' 2.切片
name_list = ['nick', 'jason', 'tank', 'sean']
print(name_list[0:3:2]) #['nick', 'tank'] 3.长度
name_list = ['nick', 'jason', 'tank', 'sean']
print(len(name_list)) # 4 4.成员运算 in 和 not in
name_list = ['nick', 'jason', 'tank', 'sean']
print('nick' in name_list) # True
print(not 'jason' in name_list) # False 5.追加值
name_list = ['nick', 'jason', 'tank', 'sean']
name_list.append('jack')
print(name_list) #['nick', 'jason', 'tank', 'sean', 'jack'] 6.删除
name_list = ['nick', 'jason', 'tank', 'sean']
del name_list[0]
print(name_list) #['jason', 'tank', 'sean'] 7.循环
name_list = ['nick', 'jason', 'tank', 'sean']
for name in name_list:
print(name)
nick
jason
tank
sean 8.插入insert(index,object) 把object插入到索引对应值的前面
name_list = ['nick', 'jason', 'tank', 'sean']
name_list.insert(1, 'handsome')
print(name_list)
['nick', 'handsome', 'jason', 'tank', 'sean'] 9.pop() 默认删除最后一个元素并且可以返回删除的元素
name_list = ['nick', 'jason', 'tank', 'sean']
s=name_list.pop(0)
print(name_list)
print(s)
['jason', 'tank', 'sean']
nick 10.count()方法，统计元素在列表中出现的次数
name_list = ['nick', 'jason', 'tank', 'sean']
print(name_list.count('nick')) # 1 11.index(),获取元素在列表中的索引
name_list = ['nick', 'jason', 'tank', 'sean']
print(name_list.index('nick')) # 0 12.clear(),清空列表
name_list = ['nick', 'jason', 'tank', 'sean']
name_list.clear()
print(name_list) # [] 13.copy()复制列表
name_list = ['nick', 'jason', 'tank', 'sean']
list2=name_list.copy()
print(list2) # ['nick', 'jason', 'tank', 'sean'] 14.extend(),扩展列表
name_list = ['nick', 'jason', 'tank', 'sean']
name_list2=['jack','mick']
name_list.extend(name_list2)
print(name_list2) #['nick', 'jason', 'tank', 'sean','jack','mick']
15.reverse()，反转列表
name_list = ['nick', 'jason', 'tank', 'sean']
name_list.reverse()
print(name_list) #['sean','tank','jason','nick'] 16.sort()，排序,列表元素必须是同类型才能排序
name_list = ['nick', 'jason', 'tank', 'sean']
name_list.sort()
print(name_list) #['jason', 'nick', 'sean', 'tank']4.存一个值或多个值
多个值，值可以是任意元素类型
5.有序或无序
有序
6.可变或不可变
可变数据类型