Pandas 比较两个数据框中的两列，如果有匹配项，则从第三列获取值转换为周数

Question

truing to automate one report, but its over my current skill level, please assist if possible. df1

report = {'Name':["one", "two", "three", "four", "five"],'Week_Num':['','','','',''],"Week_1":['1','1','','',''],"Week_2":['','1','','1',''],"Week_3":['','','','','1'],"Week_4":['','','1','',''],"Week_5":['','','','','']}

df2

data = {'Name': ["one", "two", "four", "five", "two", "three"],
    "Dates":["03/01/2022", "09/01/2022", "13/01/2022", "21/01/2022", "01/01/2022","28/01/2022"]}

Now i have to match report['Name'] with data['Name'],if there is a match to get data["Dates"] convert data["Dates"] to week_number"Today is week 18", and increase value of report.at[match, week_number] += 1 on every match. Expected output:

report = {'Name':["one", "two", "three", "four", "five"],'Week_Num':['','','','',''],"Week_1":['1','1','','',''],"Week_2":['','1','','1',''],"Week_3":['','','','','1'],"Week_4":['','','1','',''],"Week_5":['','','','','']}

Answer 1

Try with merge :

data["Week_Num"] = pd.to_datetime(data["Dates"],format="%d/%m/%Y").dt.strftime("%W").astype(int).add(1)

counts = data[["Name","Week_Num"]].merge(report["Name"], how="right").set_index("Name")
output = pd.get_dummies(counts["Week_Num"]).reindex(range(1,6),axis=1,fill_value=0).groupby(level=0).sum().reindex(report["Name"]).reset_index()

>>> output
    Name  1  2  3  4  5
0    one  0  1  0  0  0
1    two  1  1  0  0  0
2  three  0  0  0  0  1
3   four  0  0  1  0  0
4   five  0  0  0  1  0