Set value of a particular Cell:

import pandas as pd

df = pd.DataFrame({'Age': [30, 40, 30, 40, 30, 30, 20, 25],
                   'Height': [120, 162, 120, 120, 120, 72, 120, 81]},
                  index=['Jane', 'Jane', 'Aaron', 'Penelope', 'Jaane', 'Nicky',
                         'Armour', 'Ponting'])
print("\n--------------Before------------\n")
print(df)

df.iat[0, 0] = 90
df.iat[0, 1] = 91
df.iat[1, 1] = 92
df.iat[2, 1] = 93
df.iat[7, 1] = 99

print("\n--------------After------------\n")
print(df)

C:\python\examples>python example57.py
 
--------------Before------------
 
          Age  Height
Jane       30     120
Jane       40     162
Aaron      30     120
Penelope   40     120
Jaane      30     120
Nicky      30      72
Armour     20     120
Ponting    25      81
 
--------------After------------
 
          Age  Height
Jane       90      91
Jane       40      92
Aaron      30      93
Penelope   40     120
Jaane      30     120
Nicky      30      72
Armour     20     120
Ponting    25      99
 
C:\python\examples>