Create a new column in Pandas dataframe


Import modules

import pandas as pd
 

Create some dummy data

raw_data = {'name': ['Willard Morris', 'Al Jennings', 'Omar Mullins', 'Spencer McDaniel'],
'age': [20, 19, 22, 21],
'favorite_color': ['blue', 'blue', 'yellow', "green"],
'test_one': [88, 92, 95, 70],
'test_two': [78, 100, 90, 85]}
df = pd.DataFrame(raw_data)
df
age favorite_color name test_one test_two
0 20 blue Willard Morris 88 78
1 19 blue Al Jennings 92 100
2 22 yellow Omar Mullins 95 90
3 21 green Spencer McDaniel 70 85

df['test_average'] = (df.test_one + df.test_two)/2
df.head()
age favorite_color name test_one test_two test_average
0 20 blue Willard Morris 88 78 83.0
1 19 blue Al Jennings 92 100 96.0
2 22 yellow Omar Mullins 95 90 92.5
3 21 green Spencer McDaniel 70 85 77.5


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