Full guide Read Files in Python

In Python, CSV file is a plain text file that contains data in a tabular format. Each row of data is represented as a line in the file, and columns within the row are separated by a delimiter, typically a comma, but other delimiters like a semicolon or a tab can also be used. CSV files are widely used in data science and analysis to store and exchange data between different software applications. Python provides a built-in module called csv that makes it easy to read, write, and manipulate CSV files.

Read Files in Python

To work with CSV files in Python, you can use the csv module. Here’s a simple example of reading a CSV file:

Import csv

With open(‘example.csv’, ‘r’) as file:

    Reader = csv.reader(file)

    For row in reader:

        Print(row)

This code opens a CSV file named ‘example.csv’ and reads the data using the csv.reader() function. It then prints each row of data to the console. You can also use the csv.writer() function to write data to a CSV file

CSV (Comma Separated Values) files are a common data format used to store and exchange data between different systems. Python, being a versatile programming language, offers several built-in modules for reading and writing CSV files. In this article, we’ll discuss how to read CSV files in Python.

First, we’ll start with reading a CSV file.

Reading a CSV File in Python

Read csv file in python guide: Python has a built-in CSV module that provides functionality to read CSV files. The CSV module can be used to read a CSV file in two ways – using the reader object or the DictReader object.

Using the reader object

The reader object is used to read a CSV file in a list of lists format. Each row in the CSV file is represented as a list, and all the rows are stored in a list. Here’s how to use the reader object:

Import csv

# Open the CSV file

With open(‘file.csv’) as csv_file:

    # Create the reader object

    Csv_reader = csv.reader(csv_file)

    # Loop through the rows

    For row in csv_reader:

        Print(row)

In the above code, we first open the CSV file using the open() function and then create a reader object using the csv.reader() function. We then loop through the rows using a for loop and print each row.

Using the DictReader object

The DictReader object is used to read a CSV file in a dictionary format. In this format, each row is represented as a dictionary, with the keys being the column headers and the values being the data in each column. Here’s how to use the DictReader object:

Import csv

# Open the CSV file

With open(‘file.csv’) as csv_file:

    # Create the DictReader object

    Csv_dict_reader = csv.DictReader(csv_file)

    # Loop through the rows

    For row in csv_dict_reader:

       Print(row)

In the above code, we first open the CSV file using the open() function and then create a DictReader object using the csv.DictReader() function. We then loop through the rows using a for loop and print each row.

Writing a CSV File in Python

Python’s CSV module also provides functionality to write data to a CSV file. The CSV module can be used to write a CSV file in two ways – using the writer object or the DictWriter object.

Using the writer object

The writer object is used to write data to a CSV file in a list of lists format. Each row is represented as a list, and all the rows are stored in a list. Here’s how to use the writer object:

Import csv

# Data to be written

Data = [[‘John’, ‘Doe’, ‘25’],

        [‘Jane’, ‘Doe’, ‘22’],

        [‘Joe’, ‘Smith’, ‘30’]]

# Open the CSV file

With open(‘file.csv’, ‘w’, newline=’’) as csv_file:

    # Create the writer object

    Csv_writer = csv.writer(csv_file)

    # Write the data

    Csv_writer.writerows(data)

In the above code, we first create a list of lists containing the data we want to write to the CSV file. We then open the CSV file using the open() function with the mode set to ‘w’ to indicate that we want to write to the file. We also set the newline parameter to ‘’ to ensure that there are no extra blank lines in the output. We then create a writer object using the csv.writer() function and use the writerows() function to write the data to the CSV file.

Final words

Python is a high-level, interpreted programming language that has gained immense popularity in recent years. It is known for its simple and elegant syntax, which makes it easy to learn and use for both beginners and experienced programmers. Python has a wide range of applications, from web development and data analysis to machine learning and artificial intelligence.