常用方法"/>
python中列表常用方法
- 列表可以通过下标来改变元素的值
- 列表中的元素也可以是列表
- 列表中的元素种类可以不同
1.append(object)在列表尾部追加元素
#追加元素
a = ["city","kill",11,98]
a.append("python")
print(a)#追加元组
b = ["city","kill",11,98]
t = ("java","python")
b.append(t)
print(b)#追加列表
c = ["city","kill",11,98]
c.append(["java","python"])
print(c)
['city', 'kill', 11, 98, 'python']
['city', 'kill', 11, 98, ('java', 'python')]
['city', 'kill', 11, 98, ['java', 'python']]
2.insert(index,object)向指定位置添加元素
#插入元素
a = ["city","kill",11,98]
a.insert(1,'python')
print(a)#插入元组
b = ["city","kill",11,98]
t = ("java","python")
b.insert(1,t)
print(b)#插入列表
c = ["city","kill",11,98]
c.insert(3,["java","python"])
print(c)#插入字符串
d = ["city","kill",11,98]
d.insert(0,"python")
['city', 'python', 'kill', 11, 98]
['city', ('java', 'python'), 'kill', 11, 98]
['city', 'kill', 11, ['java', 'python'], 98]
3.sort()列表按照ASCLL码值从小到大排序
a = [1,3,6,8,95,5,88,47]
a.sort()
#print(a.sort())#不可一起写,sort函数修改序列,不返回任何值,打印出为None
print(a)
[1, 3, 5, 6, 8, 47, 88, 95]
注意:排序的时候列表里的元素需种类单一
4.index()查找元素位置,返回下标值
a = [1,3,6,1,8,95,5,88,47]
print(a.index(3))
1
注意:当元素有重复时,会返回该元素第一次出现的 下标值,当不存在该元素时,会报错
5.reverse()将列表进行翻转
a = [1,3,6,1,8,95,5,88,47]
a.reverse()
print(a)
[47, 88, 5, 95, 8, 1, 6, 3, 1]
6.remove()通过元素移除列表中的元素
a = [1,3,6,1,8,95,5,88,47]
a.remove(1)
print(a)
[3, 6, 1, 8, 95, 5, 88, 47]
注意:如果元素不存在则会抛出异常
7.count()统计元素出现的次数
a = [1,3,6,1,8,95,5,88,47]
print(a.count(1))
2
8.clear()清除元素
a = [1,3,6,1,8,95,5,88,47]
a.clear()
print(a)
[]
9.copy()拷贝列表
a = [1,3,6,1,8,95,5,88,47]
s = a.copy()
print(s)
[1,3,6,1,8,95,5,88,47]
10.extend()合并列表
#追加元素
a = ["city","kill",11,98]
a.extend("python")
print(a)#追加元组
b = ["city","kill",11,98]
t = ("java","python")
b.extend(t)
print(b)#追加列表
c = ["city","kill",11,98]
c.extend(["java","python"])
print(c)
['city', 'kill', 11, 98, 'p', 'y', 't', 'h', 'o', 'n']
['city', 'kill', 11, 98, 'java', 'python']
['city', 'kill', 11, 98, 'java', 'python']
11.pop()删除列表最后一个元素,有返回值,其值为删除的元素
list = ["python",1,2,"java",78,9,80,90]
print(list)
list.pop(3)
print(list)
['python', 1, 2, 'java', 78, 9, 80, 90]
['python', 1, 2, 'java', 78, 9, 80]
更多推荐
python中列表常用方法
发布评论