How to create repetitive values column (using hours) for ID numbers for each date available?-CodePudding

In the following example of a data frame:

Date	ID number
15/06/2022	1523
15/06/2022	1402

I'm trying to add a column in pandas to a the data frame that has repetitive values, such as:

Date	ID number	Hour
15/06/2022	1523	1
15/06/2022	1523	2
15/06/2022	1523	4
15/06/2022	1523	5
15/06/2022	1523	6
15/06/2022	1523	7
15/06/2022	1523	8
15/06/2022	1402	1
15/06/2022	1402	2
15/06/2022	1402	4
15/06/2022	1402	5
15/06/2022	1402	6
15/06/2022	1402	7
15/06/2022	1402	8

How is this possible please? Thanks in advance

CodePudding user response：

You can multiply and concat the df

pd.concat([df]*8).sort_values('ID number')

         Date  ID number
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
1  15/06/2022       1402
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523
0  15/06/2022       1523

CodePudding user response：

Try:

df.reindex(df.index.repeat(8)).assign(hour=np.tile(np.arange(1,9),2))

Output:

         Date  ID number  hour
0  15/06/2022       1523     1
0  15/06/2022       1523     2
0  15/06/2022       1523     3
0  15/06/2022       1523     4
0  15/06/2022       1523     5
0  15/06/2022       1523     6
0  15/06/2022       1523     7
0  15/06/2022       1523     8
1  15/06/2022       1402     1
1  15/06/2022       1402     2
1  15/06/2022       1402     3
1  15/06/2022       1402     4
1  15/06/2022       1402     5
1  15/06/2022       1402     6
1  15/06/2022       1402     7
1  15/06/2022       1402     8

And, you can add .reset_index() to get unique indexing for the rows also.