The output from this script: # python3 /tmp/dataframe_ex. # Print the AFTER content print(df.columns) This is similar to what we did in Method 3 using read_csv with names attribute #!/usr/bin/env python3ĭf.columns = But make sure the length of new column list is same as the one which you are replacing. I would not call this as rename instead you can define a new Column List and replace the existing one using columns attribute of the dataframe object. The output from this script: # python3 /tmp/dataframe_ex.pyĭefine new Column List using Panda DataFrame # Rename column labels with list assignmentsĬolumn_list = 'SUV' # Reassign the new column values This method is quite useful when we need to rename some selected columns because we need to specify information only for the columns which are to be renamed. # Store the column header and converts to list How to rename columns in Pandas DataFrame Method 1: Using rename () function One way of renaming the columns in a Pandas Dataframe is by using the rename () function. It then modifies a couple values in the list and reassigns the list to the columns attributes:.using dictionaries, normal functions or lambdas). There are multiple ways to rename columns with the rename function (e.g. The following code uses the tolist method on each Column object to create a Python list of labels. The Pandas DataFrame rename function allows to rename the labels of columns in a Dataframe using a dictionary that specifies the current and the new values of the labels.This assignment works when the list has the same number of elements as the row and column labels.It is possible to reassign the column attributes directly to a Python list.tolist() is used to convert series to list.New_columns = ĭf = pd.read_csv('/root/cars.csv', names = new_columns, header = 0 )ĪLSO READ: How to count rows in a pandas DataFrame Re-assign column attributes using tolist() # The length of the new list must be same as existing column length # Define new list with the new column names make sure that length of new list is same as the existing one in your input CSV or List #!/usr/bin/env python3 In this example we define a new list new_colums and store the new column name. Use header = 0 to remove the first header from the output If you pass extra name in this list, it will add another new column with that name with new values. Names parameter in read_csv function is used to define column names. Pandas rename columns using read_csv with names Similarly you can use str.lower to transform the Column header format to lowercase To rename multiple columns inplace we will use below syntax: (columns =, axis='columns', inplace = True)ĭf.rename(str.upper, axis='columns', inplace = True) We can pass inplace=True to rename the data in place.ĪLSO READ: Compare loc vs iloc vs at vs iat with Examples.The rename() method provides an inplace named parameter that is by default False and copies the underlying data.We can use this function to rename single or multiple columns in Python DataFrame.The rename DataFrame method accepts dictionaries that map the old value to the new value.Output from this script: # python3 /tmp/dataframe_ex.py # Print the content of cars.csv print(df) # and assign the resulting DataFrame to variable # Pass the filename to the dataset to read_csv #!/usr/bin/env python3 import pandas as pd
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