Group repeating pattern in pandas Dataframe - pandas

Question

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
8
235
1
Max of Group
5
387
2
Max of Group
7
911
2
Max of Group
3
365
3
Max of Group
4
270
3
Max of Group
5
194
3
Max of Group
7
452
3
Max of Group
100
716
4
Max of Group
104
69
4
Max of Group
2
846
5
Max of Group
3
474
5
Max of Group
4
524
5
Max of Group
So essentially the number pattern is always monotonly increasing.
Any Ideas?

Answer 1

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
For monotically increasing use:
df['Desired Group'] = (~df['Number Pattern'].diff().gt(0)).cumsum()