1.插入元素
>>> li = ['a', 'b', 'z', 'example']
>>> li.insert(2,'new')#在指定的位置插入
>>> li
['a', 'b', 'new', 'z', 'example']
>>> li.append('app')#插入到末尾
>>> li
['a', 'b', 'new', 'z', 'example', 'app']
2.extend和append
>>> li= [1,2,3]
>>> li.append([4,5])#将[]做为一个整体加进list里去
>>> li
[1, 2, 3, [4, 5]]
>>> li.extend([4,5])#将[]里的元素分别加进list里去
>>> li
[1, 2, 3, [4, 5], 4, 5]
3. slice
(start:end:step)默认值(0:list的长度:1)
>>> li = [11,22,33,44]
>>> li[:1]#从0到1
[11]
>>> li[1:]#从0到3
[22, 33, 44]
>>> li[1:3]#从1到3
[22, 33]
>>> li[::1]#从0到4,以1自加
[33, 22, 33, 44]
>>> li[::2]#从0到4,以2自加
[33, 33]
4.list 的'+'操作
>>> li = [1,2]
>>> li = li+[3]#可以用这种方式来添加到list,不过慢了点
>>> li
[1, 2, 3]
>>> li = li+[5,6]#这样的方式和extend效果差不多,不过也稍微慢一些
>>> li
[1, 2, 3, 5, 6]
>>> li2 = ['a','b']
>>> li2+li#可以直接利用加操作将两个list连接起来
['a', 'b', 1, 2, 3, 5, 6]
>>>
5.
row = [0] * 5
multi = [row] * 3
#row 是5个对0 的引用
#multi 则是3个对row的引用
#multi[0][0] = 'some'这个修改是对row这个引用的第一个元素的修改,因此会全部变化。
>>> multi[0][0] = 'some'
>>>
>>> multi
[['some', 0, 0, 0, 0], ['some', 0, 0, 0, 0], ['some', 0, 0, 0, 0]]
#如果不想创建某个list 的引用,则应用下面这样的方式
multilist = [[0 for col in range(5)] for row in range(10)]
参考:
1.《dive into python》
2.《python cookbook》
3.http://www.java2s.com/Code/Python/
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