Is it possible to add several columns at once to a pandas DataFrame?

Question

If I want to create a new DataFrame with several columns, I can add all the columns at once -- for example, as follows:

data = {\'col_1\': [0, 1, 2, 3],
             


        

Answer 1

All you need to do is create the new columns with data from the additional dataframe.

data =            {'col_1': [0, 1, 2, 3],
                   'col_2': [4, 5, 6, 7]}
additional_data = {'col_3': [8, 9, 10, 11],
                   'col_4': [12, 13, 14, 15]}
df = pd.DataFrame(data)
df2 = pd.DataFrame(additional_data)

df[df2.columns] = df2

df now looks like:

   col_1  col_2  col_3  col_4
0      0      4      8     12
1      1      5      9     13
2      2      6     10     14
3      3      7     11     15

Indices from the original dataframe will be used as if you had performed an in-place left join. Data from the original dataframe in columns with a matching name in the additional dataframe will be overwritten. For example:

data =            {'col_1': [0, 1, 2, 3],
                   'col_2': [4, 5, 6, 7]}
additional_data = {'col_2': [8, 9, 10, 11],
                   'col_3': [12, 13, 14, 15]}
df = pd.DataFrame(data)
df2 = pd.DataFrame(additional_data, index=[0,1,2,4])

df[df2.columns] = df2

df now looks like:

   col_1  col_2  col_3
0      0      8     12
1      1      9     13
2      2     10     14
3      3    NaN    NaN