While working with data in Pandas, we perform a vast array of operations on the data to get the data in the desired form. One of these operations could be that we want to remap the values of a specific column in the DataFrame. Let’s discuss several ways in which we can do that.
Given a Dataframe containing data about an event, remap the values of a specific column to a new value.
Code #1: We can use DataFrame.replace()
function to achieve this task. Let’s see how we can do that.
# importing pandas as pd import pandas as pd # Creating the DataFrame df = pd.DataFrame({ 'Date' :[ '10/2/2011' , '11/2/2011' , '12/2/2011' , '13/2/2011' ], 'Event' :[ 'Music' , 'Poetry' , 'Theatre' , 'Comedy' ], 'Cost' :[ 10000 , 5000 , 15000 , 2000 ]}) # Print the dataframe print (df) |
Output :
Now we will remap the values of the ‘Event’ column by their respective codes.
# Create a dictionary using which we # will remap the values dict = { 'Music' : 'M' , 'Poetry' : 'P' , 'Theatre' : 'T' , 'Comedy' : 'C' } # Print the dictionary print ( dict ) # Remap the values of the dataframe df.replace({ "Event" : dict }) |
Output :
Code #2: We can use map()
function to achieve this task.
# importing pandas as pd import pandas as pd # Creating the DataFrame df = pd.DataFrame({ 'Date' :[ '10/2/2011' , '11/2/2011' , '12/2/2011' , '13/2/2011' ], 'Event' :[ 'Music' , 'Poetry' , 'Theatre' , 'Comedy' ], 'Cost' :[ 10000 , 5000 , 15000 , 2000 ]}) # Print the dataframe print (df) |
Output :
Now we will remap the values of the ‘Event’ column by their respective codes.
# Create a dictionary using which we # will remap the values dict = { 'Music' : 'M' , 'Poetry' : 'P' , 'Theatre' : 'T' , 'Comedy' : 'C' } # Print the dictionary print ( dict ) # Remap the values of the dataframe df[ 'Event' ] = df[ 'Event' ]. map ( dict ) # Print the DataFrame after modification print (df) |
Output :
Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.
To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course.