列表

序列是Python中最基本的数据结构。序列中的每个元素都分配一个数字 - 它的位置，或索引，第一个索引是0，第二个索引是1，依此类推

  • 索引访问
  • 长度
  • 空或者False

创建列表的方式

a = []

a = [1,2,3]

a = list()

a = list('abcdefg')

a = list(range(10))

a = [ x for x in range(20) ]
  • append
In [17]: a=[1,2,3]

In [18]: a.append(4)

In [19]: a
Out[19]: [1, 2, 3, 4]

In [20]:
  • extend
In [21]: a
Out[21]: [1, 2, 3, 4]

In [22]: a.extend([5,6])

In [23]: a
Out[23]: [1, 2, 3, 4, 5, 6]

In [24]:
  • pop
In [25]: a
Out[25]: [1, 2, 3, 4, 5, 6]

In [26]: a.pop(2)
Out[26]: 3

In [27]: a
Out[27]: [1, 2, 4, 5, 6]

In [28]:
  • reverse (in place)
In [29]: a
Out[29]: [1, 2, 4, 5, 6]

In [30]: a.reverse()

In [31]: a
Out[31]: [6, 5, 4, 2, 1]

In [32]:
  • sort (in place)
In [51]: a
Out[51]: [6, 5, 4, 2, 1]

In [52]: a.sort()

In [53]: a
Out[53]: [1, 2, 4, 5, 6]

In [54]:
  • reversed
In [58]: a
Out[58]: [1, 2, 4, 5, 6]

In [59]: list(reversed(a))
Out[59]: [6, 5, 4, 2, 1]

In [60]:
  • sorted
In [61]: sorted(a)
Out[61]: [1, 2, 4, 5, 6]

In [62]: