Replace Values Based On Index In Pandas Dataframes

You can easily replace a value in pandas data frames by just specifying its column and its index.

import pandas as pd
import dataframe_image as dfi
 
df = pd.DataFrame({'A': [1,2,3,4],
                   'B':['A','B','C','D']})
 

Having the dataframe above, we will replace some of its values. We are using the loc function of pandas. The first variable is the index of the value we want to replace and the second is its column.

df.loc[0,"A"]=20

df.loc[1,"B"]="Billy"

The loc function also lets you set a range of indexes to be replaced as follows.

df.loc[0:2,"A"]=100