how to add columns to dataframe in pandas code example

Example 1: how to add a column to a pandas df

#using the insert function:
df.insert(location, column_name, list_of_values) 
#example
df.insert(0, 'new_column', ['a','b','c'])
#explanation:
#put "new_column" as first column of the dataframe
#and puts 'a','b' and 'c' as values

#using array-like access:
df['new_column_name'] = value

#df stands for dataframe

Example 2: how to add a new column to the pandas df

import pandas as pd

data = {'Name': ['Josh', 'Stephen', 'Drake', 'Daniel'], 
        'Height': [5.5, 6.0, 5.3, 4.9]}

'''
printing data at this point will show the following
      Name  Height
0     Josh     5.1
1  Stephen     6.2
2    Drake     5.1
3   Daniel     5.2
'''

df.insert(2, "Age", [20, 21, 20, 19])

'''
printing data now will show the following

      Name  Height  Age
0     Josh     5.1   20
1  Stephen     6.2   21
2    Drake     5.1   20
3   Daniel     5.2   19
'''

Example 3: insert new column to dataframe

group = np.random.randint(10, size=6)
df_new['Group'] = group

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Misc Example