我想找到一个现有的 col/row 并编辑它

Question

So I am developing a RFID system for a project. I am writing it on a Raspberry PI running python3.

I have these RFID tags, that you scan, and it will log the information at which it was tagged. That sums up to these columns in excel:

"worker_name": "", "date": "", "check_in_time": "", "check_out_time": "", "hours_worked": ""

---

I can fill in all these values at check-in, except for the check_out_time obviously, since that should be filled out the second time the tag is scanned.

So my problem is I have no idea on how I can edit the column, when the tag is scanned for check-out, so the check-out time is also logged in the original column, without creating a new one.

The code I have as we speak is as follows:

import pandas as pd
from datetime import datetime
from time import sleep


counter = 1

df = pd.DataFrame(
    {
        "worker": "",
        "date": "",
        "check_in_time": "",
        "check_out_time": "",
        "hours_worked": "",
    },
    index=[counter],
)

while True:

    worker = input("Navn \n")
    time_now = datetime.now()

    date = time_now.strftime("%m/%d/%Y")
    time = time_now.strftime("%H:%M")
    month = time_now.strftime("%m")

    new_check_in = [worker, date, time, "", "dummy_value"]

    df.loc[counter] = new_check_in

    df.reset_index(drop=True)
    df.to_excel("output.xlsx", index=False)

    counter += 1

Output is as follows:

     worker        date    check_in_time check_out_time  hours_worked
1  Homer Simpson  12/09/2021   02:14                     dummy_value
2  Marge Simpson  12/09/2021   02:14                     dummy_value
3   Bart Simpson  12/09/2021   02:14                     dummy_value
4  Peter Griffin  12/09/2021   02:14                     dummy_value

This is a proof of example, since I have not yet implemented the part where u scan the tag, concept should remain the same though.

So when worker at index 1, finishes his workday, he checks out with his tag, and the dataframe column storing his information, should be updated with check out time.

Thank you all, kind regards!

Answer 1

Assuming that all workers have different names, you could try checking for the worker / date values in their respective columns and fill in the check_out_time if it appears.

The latter section of your code could looks as follows, for example:

while True:

    worker = input("Navn \n")
    time_now = datetime.now()

    date = time_now.strftime("%m/%d/%Y")
    time = time_now.strftime("%H:%M")

    if ((df['worker'] == worker) & (df['date'] == date)).any():
        idx = df.iloc[(df['worker'] == worker) & (df['date'] == date)]
        df.at[idx, check_out_time] = time
        df.at[idx, hours_worked] = time - df.at[idx, check_in_time]

    new_check_in = [worker, date, time, "", np.nan]

    df.loc[counter] = new_check_in

    df.reset_index(drop=True)
    df.to_excel("output.xlsx", index=False)

    counter += 1