我有以下数据框：
Hotel_id Month_Year Chef_Id Chef_is_masterchef Transition
2400188 February-2018 4597566 1 0
2400188 March-2018 4597566 1 0
2400188 April-2018 4597566 1 0
2400188 May-2018 4597566 1 0
2400188 June-2018 4597566 1 0
2400188 July-2018 4597566 1 0
2400188 August-2018 4597566 1 0
2400188 September-2018 4597566 0 1
2400188 October-2018 4597566 0 0
2400188 November-2018 4597566 0 0
2400188 December-2018 4597566 0 0
2400188 January-2019 4597566 0 0
2400188 February-2019 4597566 0 0
2400188 March-2019 4597566 0 0
2400188 April-2019 4597566 0 0
2400188 May-2019 4597566 0 0
2400614 May-2015 2297544 0 0
2400614 June-2015 2297544 0 0
2400614 July-2015 2297544 0 0
2400614 August-2015 2297544 0 0
2400614 September-2015 2297544 0 0
2400614 October-2015 2297544 0 0
2400614 November-2015 2297544 0 0
2400614 December-2015 2297544 0 0
2400614 January-2016 2297544 1 1
2400614 February-2016 2297544 1 0
2400614 March-2016 2297544 1 0
3400624 May-2016 2597531 0 0
3400624 June-2016 2597531 0 0
3400624 July-2016 2597531 0 0
3400624 August-2016 2597531 1 1
2400133 February-2016 4597531 0 0
2400133 March-2016 4597531 0 0
2400133 April-2016 4597531 0 0
2400133 May-2016 4597531 0 0
2400133 June-2016 4597531 0 0
2400133 July-2016 4597531 0 0
2400133 August-2016 4597531 1 1
2400133 September-2016 4597531 1 0
2400133 October-2016 4597531 1 0
2400133 November-2016 4597531 1 0
2400133 December-2016 4597531 1 0
2400133 January-2017 4597531 1 0
2400133 February-2017 4597531 1 0
2400133 March-2017 4597531 1 0
2400133 April-2017 4597531 1 0
2400133 May-2017 4597531 1 0
当在 Chef_is_Masterchef 列中从 0到1 或 1到0 进行转换时，此转换会在过渡列为 1 。
实际上，我考虑过创建另一列（名称为“ Var ”），该列中的值将按照以下针对原始数据帧的说明进行填充，
期望的数据框：
Hotel_id Month_Year Chef_Id Chef_is_masterchef Transition Var
2400188 February-2018 4597566 1 0 -7
2400188 March-2018 4597566 1 0 -6
2400188 April-2018 4597566 1 0 -5
2400188 May-2018 4597566 1 0 -4
2400188 June-2018 4597566 1 0 -3
2400188 July-2018 4597566 1 0 -2
2400188 August-2018 4597566 1 0 -1
2400188 September-2018 4597566 0 1 0
2400188 October-2018 4597566 0 0 1
2400188 November-2018 4597566 0 0 2
2400188 December-2018 4597566 0 0 3
2400188 January-2019 4597566 0 0 4
2400188 February-2019 4597566 0 0 5
2400188 March-2019 4597566 0 0 6
2400188 April-2019 4597566 0 0 7
2400188 May-2019 4597566 0 0 8
2400614 May-2015 2297544 0 0 -8
2400614 June-2015 2297544 0 0 -7
2400614 July-2015 2297544 0 0 -6
2400614 August-2015 2297544 0 0 -5
2400614 September-2015 2297544 0 0 -4
2400614 October-2015 2297544 0 0 -3
2400614 November-2015 2297544 0 0 -2
2400614 December-2015 2297544 0 0 -1
2400614 January-2016 2297544 1 1 0
2400614 February-2016 2297544 1 0 1
2400614 March-2016 2297544 1 0 2
3400624 May-2016 2597531 0 0 -3
3400624 June-2016 2597531 0 0 -2
3400624 July-2016 2597531 0 0 -1
3400624 August-2016 2597531 1 1 0
2400133 February-2016 4597531 0 0 -6
2400133 March-2016 4597531 0 0 -5
2400133 April-2016 4597531 0 0 -4
2400133 May-2016 4597531 0 0 -3
2400133 June-2016 4597531 0 0 -2
2400133 July-2016 4597531 0 0 -1
2400133 August-2016 4597531 1 1 0
2400133 September-2016 4597531 1 0 1
2400133 October-2016 4597531 1 0 2
2400133 November-2016 4597531 1 0 3
2400133 December-2016 4597531 1 0 4
2400133 January-2017 4597531 1 0 5
2400133 February-2017 4597531 1 0 6
2400133 March-2017 4597531 1 0 7
2400133 April-2017 4597531 1 0 8
2400133 May-2017 4597531 1 0 9
如果观察到的话，在 Var 列中的过渡点处，我将该值设为零，并在保持相应整数值之前和之后的各行中给出该值。
但是使用下面的代码后，我在Var列中遇到了问题，
s = df['Chef_is_masterchef'].eq(0).groupby(df['Chef_Id']).transform('sum')
df['var'] = df.groupby('Chef_Id').cumcount().sub(s)
上述代码的输出：
Hotel_id Month_Year Chef_Id Chef_is_masterchef Transition Var
2400188 February-2018 4597566 1 0 -9
2400188 March-2018 4597566 1 0 -8
2400188 April-2018 4597566 1 0 -7
2400188 May-2018 4597566 1 0 -6
2400188 June-2018 4597566 1 0 -5
2400188 July-2018 4597566 1 0 -4
2400188 August-2018 4597566 1 0 -3
2400188 September-2018 4597566 0 1 -2
2400188 October-2018 4597566 0 0 -1
2400188 November-2018 4597566 0 0 0
2400188 December-2018 4597566 0 0 1
2400188 January-2019 4597566 0 0 2
2400188 February-2019 4597566 0 0 3
2400188 March-2019 4597566 0 0 4
2400188 April-2019 4597566 0 0 5
2400188 May-2019 4597566 0 0 6
2400614 May-2015 2297544 0 0 -8
2400614 June-2015 2297544 0 0 -7
2400614 July-2015 2297544 0 0 -6
2400614 August-2015 2297544 0 0 -5
2400614 September-2015 2297544 0 0 -4
2400614 October-2015 2297544 0 0 -3
2400614 November-2015 2297544 0 0 -2
2400614 December-2015 2297544 0 0 -1
2400614 January-2016 2297544 1 1 0
2400614 February-2016 2297544 1 0 1
2400614 March-2016 2297544 1 0 2
3400624 May-2016 2597531 0 0 -3
3400624 June-2016 2597531 0 0 -2
3400624 July-2016 2597531 0 0 -1
3400624 August-2016 2597531 1 1 0
2400133 February-2016 4597531 0 0 -6
2400133 March-2016 4597531 0 0 -5
2400133 April-2016 4597531 0 0 -4
2400133 May-2016 4597531 0 0 -3
2400133 June-2016 4597531 0 0 -2
2400133 July-2016 4597531 0 0 -1
2400133 August-2016 4597531 1 1 0
2400133 September-2016 4597531 1 0 1
2400133 October-2016 4597531 1 0 2
2400133 November-2016 4597531 1 0 3
2400133 December-2016 4597531 1 0 4
2400133 January-2017 4597531 1 0 5
2400133 February-2017 4597531 1 0 6
2400133 March-2017 4597531 1 0 7
2400133 April-2017 4597531 1 0 8
2400133 May-2017 4597531 1 0 9
如果观察到的话，对于Chef_Id = 4597566，您可以看到在过渡点的值在Var列中是不同的，而不是零。
这造成了一个问题，因为在过渡时，我必须为每个id选择包括最多3个月之前和2个月之后的行。同样在过渡时，我必须使用以下代码为每个ID选择包括最长6个月之前和5个月之后的行：
df1 = df[df['var'].between(-3, 2)]
print (df1)
df2 = df[df['var'].between(-6, 5)]
print (df2)
所以请让我知道解决方法。
谢谢！
答案 0 :(得分：1)
将GroupBy.cumcount用于每组的计数器，然后通过与0和GroupBy.transform进行比较来减去0值的数量：
s = df['Chef_is_masterchef'].eq(0).groupby(df['Chef_Id']).transform('sum')
df['var'] = df.groupby('Chef_Id').cumcount().sub(s)
print (df)
Hotel_id Month_Year Chef_Id Chef_is_masterchef Transition var
0 2400614 May-2015 2297544 0 0 -8
1 2400614 June-2015 2297544 0 0 -7
2 2400614 July-2015 2297544 0 0 -6
3 2400614 August-2015 2297544 0 0 -5
4 2400614 September-2015 2297544 0 0 -4
5 2400614 October-2015 2297544 0 0 -3
6 2400614 November-2015 2297544 0 0 -2
7 2400614 December-2015 2297544 0 0 -1
8 2400614 January-2016 2297544 1 1 0
9 2400614 February-2016 2297544 1 0 1
10 2400614 March-2016 2297544 1 0 2
11 3400624 May-2016 2597531 0 0 -3
12 3400624 June-2016 2597531 0 0 -2
13 3400624 July-2016 2597531 0 0 -1
14 3400624 August-2016 2597531 1 1 0
15 2400133 February-2016 4597531 0 0 -6
16 2400133 March-2016 4597531 0 0 -5
17 2400133 April-2016 4597531 0 0 -4
18 2400133 May-2016 4597531 0 0 -3
19 2400133 June-2016 4597531 0 0 -2
20 2400133 July-2016 4597531 0 0 -1
21 2400133 August-2016 4597531 1 1 0
22 2400133 September-2016 4597531 1 0 1
23 2400133 October-2016 4597531 1 0 2
24 2400133 November-2016 4597531 1 0 3
25 2400133 December-2016 4597531 1 0 4
26 2400133 January-2017 4597531 1 0 5
27 2400133 February-2017 4597531 1 0 6
28 2400133 March-2017 4597531 1 0 7
29 2400133 April-2017 4597531 1 0 8
30 2400133 May-2017 4597531 1 0 9
最后Series.between个过滤器：
df1 = df[df['var'].between(-3, 2)]
print (df1)
df2 = df[df['var'].between(-6, 5)]
print (df2)