Python-2.7.12list类型

Posted 2020-10-06

list是Python中的一种数据类型，也就是"列表"。在Python中我们可以对list类型进行插入，删除，修改等操作。

##新建list类型
>>> ball = [‘volleyball‘,‘basketball‘,‘football‘,‘baseball‘]

##可以直接打印出list内容
>>> ball
[‘volleyball‘, ‘basketball‘, ‘football‘, ‘baseball‘]

##也可以使用下标列出，注意下标是从0开始的,负数表示从后往前数
>>> ball[0]
‘volleyball‘
>>> ball[1]
‘basketball‘
>>> ball[2]
‘football‘

##使用append函数，在list最后追加内容
>>> ball.append(‘ping-pong‘)
>>> ball
[‘volleyball‘, ‘basketball‘, ‘football‘, ‘baseball‘, ‘ping-pong‘]

##选择位置插入，比如在‘volleyball‘后面插入‘badminton‘
>>> ball.insert(1,‘badminton‘)
>>> ball
[‘volleyball‘, ‘badminton‘, ‘basketball‘, ‘football‘, ‘baseball‘, ‘ping-pong‘]

##替换list中的某一个元素，比如把‘badminton‘替换成‘bowling‘
>>> ball[1]=‘bowling‘
>>> ball
[‘volleyball‘, ‘bowling‘, ‘basketball‘, ‘football‘, ‘baseball‘, ‘ping-pong‘]

##使用pop()删除元素，比如删除最后的‘ping-pong‘，删除‘bowling‘
>>> ball.pop()
‘ping-pong‘
>>> ball
[‘volleyball‘, ‘bowling‘, ‘basketball‘, ‘football‘, ‘baseball‘]
>>> ball.pop(1)
‘bowling‘
>>> ball
[‘volleyball‘, ‘basketball‘, ‘football‘, ‘baseball‘]

##使用len()查询list中元素个数
>>> ball
[‘volleyball‘, ‘basketball‘, ‘football‘, ‘baseball‘]
>>> len(ball)
4