需要单个列中每个名称的 cumsum [重复]

Question

我需要 df['Name'] 列中每个名称的累积总和，但是当新名称出现在列中时，我需要重置计数。我将如何在熊猫中实现这一点？我用df.cumsum、df.rolling 等尝试了各种方法，但都没有成功。

Name
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Devonta Freeman
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown
Antonio Brown

期望的输出：

Name    Count
Devonta Freeman 1
Devonta Freeman 2
Devonta Freeman 3
Devonta Freeman 4
Devonta Freeman 5
Devonta Freeman 6
Devonta Freeman 7
Devonta Freeman 8
Devonta Freeman 9
Devonta Freeman 10
Devonta Freeman 11
Devonta Freeman 12
Devonta Freeman 13
Devonta Freeman 14
Devonta Freeman 15
Antonio Brown   1
Antonio Brown   2
Antonio Brown   3
Antonio Brown   4
Antonio Brown   5
Antonio Brown   6
Antonio Brown   7
Antonio Brown   8
Antonio Brown   9
Antonio Brown   10
Antonio Brown   11
Antonio Brown   12
Antonio Brown   13
Antonio Brown   14
Antonio Brown   15
Antonio Brown   16
Antonio Brown   17

Answer 1

您正在寻找cumcount。

df['Count'] = df.groupby('Name').cumcount()

输出：

>>> df
               Name  Count
0   Devonta Freeman      1
1   Devonta Freeman      2
2   Devonta Freeman      3
3   Devonta Freeman      4
4   Devonta Freeman      5
5   Devonta Freeman      6
6   Devonta Freeman      7
7   Devonta Freeman      8
8   Devonta Freeman      9
9   Devonta Freeman     10
10  Devonta Freeman     11
11  Devonta Freeman     12
12  Devonta Freeman     13
13  Devonta Freeman     14
14  Devonta Freeman     15
15    Antonio Brown      1
16    Antonio Brown      2
17    Antonio Brown      3
18    Antonio Brown      4
19    Antonio Brown      5
20    Antonio Brown      6
21    Antonio Brown      7
22    Antonio Brown      8
23    Antonio Brown      9
24    Antonio Brown     10
25    Antonio Brown     11
26    Antonio Brown     12
27    Antonio Brown     13
28    Antonio Brown     14
29    Antonio Brown     15
30    Antonio Brown     16
31    Antonio Brown     17