Pandas DataFrame: Insert a new column in existing DataFrame

Last update on May 28 2022 13:40:31 (UTC/GMT +8 hours)

Pandas: DataFrame Exercise-20 with Solution

Write a Pandas program to insert a new column in existing DataFrame.

Sample DataFrame:
Sample Python dictionary data and list labels:
exam_data = {'name': ['Anastasia', 'Dima', 'Katherine', 'James', 'Emily', 'Michael', 'Matthew', 'Laura', 'Kevin', 'Jonas'],
'score': [12.5, 9, 16.5, np.nan, 9, 20, 14.5, np.nan, 8, 19],
'attempts': [1, 3, 2, 3, 2, 3, 1, 1, 2, 1],
'qualify': ['yes', 'no', 'yes', 'no', 'no', 'yes', 'yes', 'no', 'no', 'yes']}
labels = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j']

Sample Solution :

Python Code :

import pandas as pd
import numpy as np
exam_data  = {'name': ['Anastasia', 'Dima', 'Katherine', 'James', 'Emily', 'Michael', 'Matthew', 'Laura', 'Kevin', 'Jonas'],
        'score': [12.5, 9, 16.5, np.nan, 9, 20, 14.5, np.nan, 8, 19],
        'attempts': [1, 3, 2, 3, 2, 3, 1, 1, 2, 1],
        'qualify': ['yes', 'no', 'yes', 'no', 'no', 'yes', 'yes', 'no', 'no', 'yes']}
labels = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j']
df = pd.DataFrame(exam_data , index=labels)
print("Original rows:")
print(df)
color = ['Red','Blue','Orange','Red','White','White','Blue','Green','Green','Red']
df['color'] = color
print("\nNew DataFrame after inserting the 'color' column")
print(df)

Sample Output:

Original rows:                                                          
   attempts       name qualify  score                                  
a         1  Anastasia     yes   12.5                                  
b         3       Dima      no    9.0                                  
c         2  Katherine     yes   16.5                                  
d         3      James      no    NaN                                  
e         2      Emily      no    9.0                                  
f         3    Michael     yes   20.0                                  
g         1    Matthew     yes   14.5                                  
h         1      Laura      no    NaN                                  
i         2      Kevin      no    8.0                                  
j         1      Jonas     yes   19.0                                  
                                                                       
New DataFrame after inserting the 'color' column                       
   attempts       name qualify  score   color                          
a         1  Anastasia     yes   12.5     Red                          
b         3       Dima      no    9.0    Blue                          
c         2  Katherine     yes   16.5  Orange                          
d         3      James      no    NaN     Red
e         2      Emily      no    9.0   White                          
f         3    Michael     yes   20.0   White                          
g         1    Matthew     yes   14.5    Blue                          
h         1      Laura      no    NaN   Green                          
i         2      Kevin      no    8.0   Green                          
j         1      Jonas     yes   19.0     Red

Python-Pandas Code Editor:

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Previous: Write a Pandas program to delete the 'attempts' column from the DataFrame.
Next: Write a Pandas program to iterate over rows in a DataFrame.

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