如何根据 pandas dataframe 中的匹配条件对整行进行 append？

Question

I have a dataframe which looks like the:

import pandas as pd
df_ref = pd.DataFrame({'district':['A Nzo DM','A Nzo DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM'],
'visit_date':['2021-07-31','2021-07-31','2021-07-31','2021-07-31','2021-08-31','2021-08-31','2021-08-31'],
'province':['EC','EC','NC','NC','NC','NC','NC'],
'age_group':['35-49','50-59','18-34','35-49','18-34','35-49','Unidentified'],
'sex':['Male','Female','Female','Male','Female','Male','Female'],
'vaccinations':[1,5,6,8,9,10,14]})

The data is going to be used in data visualization software I need each district for each 'visit_date (already sampled to month) to be mapped [![enter image description here][1]][1] whereby each Sex (Male and Female) has these age groups mapped to it (18-34,35-49,50-59,60+,Unidentified) for each month = ( visit_date`). The result would be:

maz = {'district':['A Nzo DM','A Nzo DM','A Nzo DM','A Nzo DM','A Nzo DM',
'A Nzo DM','A Nzo DM','A Nzo DM','A Nzo DM','A Nzo DM',
'uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM',
'uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM',
'uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM',
'uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM','uMgungundlovu DM'],
'visit_date':['2021-07-31','2021-07-31','2021-07-31','2021-07-31','2021-07-31',
                '2021-07-31','2021-07-31','2021-07-31','2021-07-31','2021-07-31',
                '2021-07-31','2021-07-31','2021-07-31','2021-07-31','2021-07-31',
                '2021-07-31','2021-07-31','2021-07-31','2021-07-31','2021-07-31',
                '2021-08-31','2021-08-31','2021-08-31','2021-08-31','2021-08-31',
                '2021-08-31','2021-08-31','2021-08-31','2021-08-31','2021-08-31'],
'province':['EC','EC','EC','EC','EC',
            'EC','EC','EC','EC','EC',
            'NC','NC','NC','NC','NC',
            'NC','NC','NC','NC','NC',
            'NC','NC','NC','NC','NC',
            'NC','NC','NC','NC','NC'],
'age_group':['18-34','35-49','50-59','60+','Unidentified',
                '18-34','35-49','50-59','60+','Unidentified',
                '18-34','35-49','50-59','60+','Unidentified',
                '18-34','35-49','50-59','60+','Unidentified',
                '18-34','35-49','50-59','60+','Unidentified',
                '18-34','35-49','50-59','60+','Unidentified'],
'sex':['Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female','Male','Female',
       'Male','Female'],}
df_output = pd.DataFrame(maz)

Answer 1

IIUC, you need a product of 'age_group' and 'sex' columns and then a 'cross' merge with rest of the columns and then drop duplicates

t = pd.DataFrame(
    itertools.product(df_ref["age_group"], df_ref["sex"]), columns=["age_group", "sex"]
).drop_duplicates(ignore_index=True)
out = pd.merge(
    df_ref[["district", "visit_date", "province"]], t, how="cross"
).drop_duplicates(ignore_index=True)

print(out):

Note: This doesn't have 60+ because input dataframe doesn't have it.

            district  visit_date province     age_group     sex
0           A Nzo DM  2021-07-31       EC         35-49    Male
1           A Nzo DM  2021-07-31       EC         35-49  Female
2           A Nzo DM  2021-07-31       EC         50-59    Male
3           A Nzo DM  2021-07-31       EC         50-59  Female
4           A Nzo DM  2021-07-31       EC         18-34    Male
5           A Nzo DM  2021-07-31       EC         18-34  Female
6           A Nzo DM  2021-07-31       EC  Unidentified    Male
7           A Nzo DM  2021-07-31       EC  Unidentified  Female
8   uMgungundlovu DM  2021-07-31       NC         35-49    Male
9   uMgungundlovu DM  2021-07-31       NC         35-49  Female
10  uMgungundlovu DM  2021-07-31       NC         50-59    Male
11  uMgungundlovu DM  2021-07-31       NC         50-59  Female
12  uMgungundlovu DM  2021-07-31       NC         18-34    Male
13  uMgungundlovu DM  2021-07-31       NC         18-34  Female
14  uMgungundlovu DM  2021-07-31       NC  Unidentified    Male
15  uMgungundlovu DM  2021-07-31       NC  Unidentified  Female
16  uMgungundlovu DM  2021-08-31       NC         35-49    Male
17  uMgungundlovu DM  2021-08-31       NC         35-49  Female
18  uMgungundlovu DM  2021-08-31       NC         50-59    Male
19  uMgungundlovu DM  2021-08-31       NC         50-59  Female
20  uMgungundlovu DM  2021-08-31       NC         18-34    Male
21  uMgungundlovu DM  2021-08-31       NC         18-34  Female
22  uMgungundlovu DM  2021-08-31       NC  Unidentified    Male
23  uMgungundlovu DM  2021-08-31       NC  Unidentified  Female