How do I concat train and test data if on the test one column is not present but I still want to keep that column present since my code doesnt work
test_df['sales'] = float('nan')
combined_df = pd.concat([train_df, test_df], axis=0)
test_df['sales'] = float('nan')
combined_df = pd.concat([train_df, test_df], axis=0)
I was expecting the sales from the train data not to be 0 as well but the whole sales column is 0 now