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: Using pandas.dataframe.at Method
This method is used to set the value for existing value or set a new record.
Syntax:
dataframe.at[index, 'column_name'] = value
where,
- dataframe is the input dataframe
- index is the position to insert
- column_name is the column where value is inserted
- value is the value to be inserted
Example:
Python3
# import pandas module import pandas as pd # create a dataframe # with 3 rows amd 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 # set value at 4 th location for name column data.at[ 4 , 'name' ] = 'siva nagulu' # set value at 4 th location for subjects column data.at[ 4 , 'subjects' ] = 'react-js' # set value at 4 th location for marks column data.at[ 4 , 'marks' ] = 80 # display data |
Output:
Method 2: Using loc() method
Here we are using loc() method to set the column value based on row index and column name
Syntax:
dataframe.loc[index, 'column_name'] = value
where,
- dataframe is the input dataframe
- index is the position to insert
- column_name is the column where value is inserted
- value is the value to be inserted
Example:
Python3
# import pandas module import pandas as pd # create a dataframe # with 3 rows amd 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.loc[ 5 , 'name' ] = 'sri devi' # set value at 6 th location for subjects column data.loc[ 5 , 'subjects' ] = 'jsp' # set value at 6 th location for marks column data.loc[ 5 , 'marks' ] = 100 # set value at 4 th location for name column 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: