Fill a matrix from another Dataframe

Question

I'm a Python beginner.

I'm encountering a problem during my loop to fill an absence matrix.

The absence matrix:

The index represents the date from the beginning of 2020 to today and the columns represent the USER IDs .

The dataframe is as follows:

ID_USER  NOM      PRENOM      DATE_first         DATE_last
1        X        X           30/05/2020 00:00   01/06/2020 23:59
1        X        X           01/06/2020 00:00   02/06/2020 23:59
2        X        X           01/06/2020 00:00   03/06/2020 23:59

and the result I want:

DATE          user1    user2
29/05/2020    0        0
30/05/2020    1        0
01/06/2020    1        1
02/06/2020    1        1
03/06/2020    0        1

The objective is to fill the absence matrix with 1 and 0 . 1 when the ID is absent between DATE_DEBUT_ABSENCE and DATE_FIN_ABSENCE .

Exemple :

• if in Dataframe ID_USER=1 was absent between 2020/01/01 and 2020/01/05 :
• in the absence of matrice in columns = 1
• index : 2020/01/01 = 1
• 2020/01/02 = 1
• 2020/01/03 = 1
• 2020/01/04 = 1
• 2020/01/05 = 1

Here is the code I started :

for i in agenda.columns:
    for j  in absence_df.ID_USER:
        if i==j and  agenda.index[i]==absence_df.iloc[j,4]:
            agenda.index[i]==1
        else :
            print('false')
    j=j+1 
    i= i+1          
    break  
                    
    print(agenda)

Answer 1

I'm assuming here your dates are in the datetime format, though I'm not sure this will work at first try (dates are tricky in python). It would be better if you could share a sample of the dataset, instead of just a snapchot...

import datetime
import pandas as pd

start = datetime.date(2020, 1, 1)
end = datetime.date(2020,1,5)
daterange = pd.date_range(start, end)

users = sorted(list(set(df.ID_USER)))

agenda = pd.DataFrame(index=daterange, columns=users)
agenda.fillna(0, inplace=True)

for date in date_range:
  ix = df[
    (df.DATE_first < date) & (date < df.DATE_last)
  ].index
  users_absent = df.loc[ix, 'ID_USER'].tolist()
  agent.loc[date, users_absent] = 1