How to add minutes to datetime64 object in a Pandas Dataframe

Question

I want to add a list of minutes to datetime64 columns into a new df column.

I tried using datetime.timedelta(minutes=x) in a for loop. But as a result, it is adding a constant value to all of my rows. How do I resolve this?

for x in wait_min:
    data['New_datetime'] = data['Date'] + datetime.timedelta(minutes=x)

I expect to iterate through the list and add corresponding minutes, but this is adding a constant value of 16 minutes to each row.

You are looping on `wait_min` but setting the entire column each loop. What is is in `wait_min`? — Stephen Rauch, Aug 03 '19 at 01:13
wait_min = list of 50 different values of minutes i want to add. for ex 10 min in first row, 20 in next and so on.. — Rick707, Aug 03 '19 at 01:17
So. You should fix the question to show all of the information. Then the experts here, might be able to help you. — Stephen Rauch, Aug 03 '19 at 01:18
Are you going to share the solution? The point of Stackoverflow is not to solve your problem, but to solve the next person's problem. Those of us who are active here are trying to generate good karma by sharing our knowledge. Can you do the same? — Stephen Rauch, Aug 03 '19 at 01:34
Thanks for letting me know. I just posted below what worked for me. Thank you stephen — Rick707, Aug 03 '19 at 01:40

score 4 · Answer 1 · answered Aug 03 '19 at 02:01

4

Let us try

data['Date'] + pd.to_timedelta(wait_min, unit='m')

answered Aug 03 '19 at 02:01

BENY

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score 1 · Answer 2 · edited Aug 03 '19 at 01:41

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The following changes worked for me:

for i, x in enumerate(wait_min):
     data['New_Datetime'].iloc[i] = data['Date'].iloc[i] + datetime.timedelta(minutes=x)

might not be the best solution, but this works for what I was trying to do.

edited Aug 03 '19 at 01:41

Stephen Rauch

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answered Aug 03 '19 at 01:39

Rick707

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score 1 · Accepted Answer · answered Aug 03 '19 at 01:44

1

pandas sums two Series element-wise, if they have the same length. All you need to do is create a Series of timedelta objects.

So if wait_min is a list of minutes of length equal to the number of rows in your dataframe, this will do:

data['New_datetime'] = data['Date'] + pd.Series([datetime.timedelta(minutes=x) for x in wait_min])

answered Aug 03 '19 at 01:44

Valentino

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Thanks valentino. This seems more efficient. I will try this. – Rick707 Aug 03 '19 at 01:46
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@Valentino, I personally make it a habit to upvote questions I answered. I think that if a question is worth answering, it is worth an upvote. In addition, the OP can not upvote your answer until they have 15 reputation. So I suggest helping them along their path to becoming good Stack Overflow citizens, by upvoting their good quesions. Cheers. – Stephen Rauch Aug 03 '19 at 02:01

How to add minutes to datetime64 object in a Pandas Dataframe

3 Answers3