[FIXED] Group repeating pattern in pandas Dataframe

Issue

so i have a Dataframe that has a repeating Number Series that i want to group like this:

Number Pattern	Value	Desired Group	Value.1
1	723	1	Max of Group
2	400	1	Max of Group
3	235	1	Max of Group
1	387	2	Max of Group
2	911	2	Max of Group
1	365	3	Max of Group
2	270	3	Max of Group
3	194	3	Max of Group
4	452	3	Max of Group
1	716	4	Max of Group
2	69	4	Max of Group
1	846	5	Max of Group
2	474	5	Max of Group
3	524	5	Max of Group

Any Ideas?

Solution

You can compare Number Pattern by 1 with cumulative sum by Series.cumsum and then is used GroupBy.transform with max:

df['Desired Group'] = df['Number Pattern'].eq(1).cumsum()
df['Value.1'] = df.groupby('Desired Group')['Value'].transform('max')
print (df)
    Number Pattern  Value  Desired Group  Value.1
0                1    723              1      723
1                2    400              1      723
2                3    235              1      723
3                1    387              2      911
4                2    911              2      911
5                1    365              3      452
6                2    270              3      452
7                3    194              3      452
8                4    452              3      452
9                1    716              4      716
10               2     69              4      716
11               1    846              5      846
12               2    474              5      846
13               3    524              5      846

Answered By - jezrael