How to append a list into a Dataframe-CodePudding

I want to populate a DataFrame with a date that the Dataframe was ran.

I can populate that data like so:

initial_test_data = pd.DataFrame(dfv, columns = [
    'result_video_views',
    'result_video_likes', 
    'result_video_comments'
    ])

initial_test_data[['date']] = [pd.to_datetime('today').strftime("%m/%d/%Y")]

I get:

    result_video_views  result_video_likes  result_video_comments   date
      0 32103                   2928                    367                 12/24/2022

My issue is that I want the date to be in the first column. I understand you can rearrange the columns but I would like to know how how to do the reverse.

Whenever I try and execute:

time = pd.to_datetime('today').strftime("%m/%d/%Y")

time[['result_video_views', etc..] = [initial_test_data]

The reverse of the above, I get "TypeError: 'str' object does not support item assignment."

I want to know how to add lists of data as columns into established DataFrames. In order to get around the type error, is this going to need a loop? I've got over 2,000 lines of data and I'm worried if I start adding too many loops I'm going to bog the program down.

CodePudding user response：

Having created the data column using:

initial_test_data[['date']] = [pd.to_datetime('today').strftime("%m/%d/%Y")]

You can change the order to put date first using:

initial_test_data = initial_test_data.reindex( columns = ['date','result_video_views', 'result_video_likes', 'result_video_comments'])

What do you mean by 'the reverse

CodePudding user response：

you can use insert() and you fixe position of date

initial_test_data.insert(0,'date',pd.to_datetime('today').strftime("%m/%d/%Y"))