Create DF Columns Based on Second DDF

I have 2 dataframes with different columns:

DF A -                   DF B - 
number | a  | b  | c  |||| a  | c  | d  | e  | f
1      | 12 | 13 | 15 |||| 22 | 33 | 44 | 55 | 77

I would like to add the missing columns for the 2 dataframes – so each one will have each own columns + the other DFs columns (without column “number”). And the new columns will have initial number for our choice (let’s say 0).
So the final output:

    DF A -                    
    number | a  | b  | c  | d  | e  | f 
    1      | 12 | 13 | 15 | 0  | 0  | 0 
    DF B -
    a  | b  | c  | d  | e  | f
    22 | 0  | 33 | 44 | 55 | 77

What’s the best way to achieve this result? I’ve got messed up with getting the columns and trying to create new ones.

Thank!

Answer

First, you need to create a superset of all the columns which are present in both the dataframes. This you can do using the below code.

all_columns = list(set(A.columns.to_list() + B.columns.to_list()))

Then for each dataframes, you need to check which columns are missing that you can do using the below code.

col_missing_from_A = [col for col in all_columns if col not in A.columns]
col_missing_from_B = [col for col in all_columns if col not in B.columns]

Then add the missing columns in both the dataframes

A[col_missing_from_A] = 0
A[col_missing_from_B] = 0

Hope this solves your query!