How to Set Cell Value in Pandas DataFrame?

In this article, we will discuss how to set cell values in Pandas DataFrame in Python.

Method 1: Set value for a particular cell in pandas using dataframe.at

This method is used to set the value of an existing value or set a new record.

Python3

# import pandas module
import pandas as pd

# create a dataframe
# with 3 rows and 3  columns
data = pd.DataFrame({
    'name': ['sireesha', 'ravi', 'rohith', 'pinkey', 'gnanesh'],
    'subjects': ['java', 'php', 'html/css', 'python', 'R'],
    'marks': [98, 90, 78, 91, 87]
})

# set value at 6 th location for name column
data.at[5, 'name'] = 'sri devi'

# set value at 6 th location for subjects column
data.at[5, 'subjects'] = 'jsp'


# set value at 6 th location for marks column
data.at[5, 'marks'] = 100

# display
data

Output:

Method 2: Set value for a particular cell in pandas using loc() method

Here we are using the Pandas loc() method to set the column value based on row index and column name

Python3

# create a dataframe
# with 3 rows and 3  columns
data = pd.DataFrame({
    'name': ['sireesha', 'ravi', 'rohith', 'pinkey', 'gnanesh'],
    'subjects': ['java', 'php', 'html/css', 'python', 'R'],
    'marks': [98, 90, 78, 91, 87]
})

data.loc[4, 'name'] = 'siva nagulu'

# set value at 4 th location for subjects column
data.loc[4, 'subjects'] = 'react-js'


# set value at 4 th location for marks column
data.loc[4, 'marks'] = 80

# display
data

Output:

Method 3: Update the value for a particular cell in pandas using replace

Here, we are updating the “suraj” value to “geeks” using Pandas replace.

Python3

# import pandas module
import pandas as pd

data.replace("suraj", "geeks", inplace=True)

#display
display(data)

Output:

Method 4: Update the value for a particular cell in pandas using iloc

Here, we are updating the value of multiple indexes of the 0_th column to 45 using Python iloc.

Python3

# import pandas module
import pandas as pd

data.iloc[[0,1,3],[0]] = 45

#display
display(data)

Output: