Replacing column value of a CSV file in Python
Let us see how we can replace the column value of a CSV file in Python. CSV file is nothing but a comma-delimited file.
Method 1: Using Native Python way
Using replace() method, we can replace easily a text into another text. In the below code, let us have an input CSV file as “csvfile.csv” and be opened in “read” mode. The join() method takes all lines of a CSV file in an iterable and joins them into one string. Then, we can use replace() method on the entire string and can perform single/multiple replacements. In the entire string, the given text is searched and replaced with the specified text.
Example:
The input file will be:
Python3
# reading the CSV filetext = open("csvfile.csv", "r") #join() method combines all contents of # csvfile.csv and formed as a stringtext = ''.join([i for i in text]) # search and replace the contentstext = text.replace("EmployeeName", "EmpName") text = text.replace("EmployeeNumber", "EmpNumber") text = text.replace("EmployeeDepartment", "EmpDepartment") text = text.replace("lined", "linked") # output.csv is the output file opened in write modex = open("output.csv","w") # all the replaced text is written in the output.csv filex.writelines(text)x.close() |
Output:
Method 2: Using Pandas DataFrame
We can read the CSV file as a DataFrame and then apply the replace() method.
Python3
# importing the moduleimport pandas as pd # making data frame from the csv file dataframe = pd.read_csv("csvfile1.csv") # using the replace() methoddataframe.replace(to_replace ="Fashion", value = "Fashion industry", inplace = True)dataframe.replace(to_replace ="Food", value = "Food Industry", inplace = True)dataframe.replace(to_replace ="IT", value = "IT Industry", inplace = True) # writing the dataframe to another csv filedataframe.to_csv('outputfile.csv', index = False) |
Output:
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