You can use the following methods to find the max value across multiple columns in a pandas DataFrame:

Method 1: Find Max Value Across Multiple Columns

df[['col1', 'col2', 'col3']].max(axis=1)

Method 2: Add New Column Containing Max Value Across Multiple Columns

df['new_col'] = df[['col1', 'col2', 'col3']].max(axis=1)

The following examples show how to use each of these methods in practice with the following pandas DataFrame:

import pandas as pd

#create DataFrame
df = pd.DataFrame({'player': ['A', 'B', 'C', 'D', 'E', 'F', 'G'],
                   'points': [28, 17, 19, 14, 23, 26, 5],
                   'rebounds': [5, 6, 4, 7, 14, 12, 9],
                   'assists': [10, 13, 7, 8, 4, 5, 8]})

#view DataFrame
print(df)

  player  points  rebounds  assists
0      A      28         5       10
1      B      17         6       13
2      C      19         4        7
3      D      14         7        8
4      E      23        14        4
5      F      26        12        5
6      G       5         9        8

Example 1: Find Max Value Across Multiple Columns

The following code shows how to find the max value in each row across the points and rebounds columns:

#find max value across points and rebounds columns
df[['points', 'rebounds']].max(axis=1)

0    28
1    17
2    19
3    14
4    23
5    26
6     9
dtype: int64

Here’s how to interpret the output:

• The max value across the points and rebounds columns for the first row was 28.
• The max value across the points and rebounds columns for the second row was 17.
• The max value across the points and rebounds columns for the third row was 19.

And so on.

Example 2: Add New Column Containing Max Value Across Multiple Columns

The following code shows how to add a new column to the DataFrame that contains the max value in each row across the points and rebounds columns:

#add new column that contains max value across points and rebounds columns
df['max_points_rebs'] = df[['points', 'rebounds']].max(axis=1)

#view updated DataFrame
print(df)

  player  points  rebounds  assists  max_points_rebs
0      A      28         5       10               28
1      B      17         6       13               17
2      C      19         4        7               19
3      D      14         7        8               14
4      E      23        14        4               23
5      F      26        12        5               26
6      G       5         9        8                9

The new column titled max_points_rebs now contains the max value across the points and rebounds columns for each row in the DataFrame.

The following tutorials explain how to perform other common tasks in pandas: