Understanding CSV Data in Python
CSV (Comma-Separated Values) is a widely used file format for storing and exchanging tabular data. In Python, the built-in csv
module provides a convenient way to work with CSV files.
What is a CSV File?
A CSV file is a plain-text file that stores data in a tabular format, where each row represents a record, and each column represents a field or attribute of that record. The values in each row are separated by a delimiter, typically a comma (,
), but other delimiters such as semicolons (;
) or tabs (\t
) can also be used.
Accessing CSV Data in Python
To work with CSV data in Python, you can use the csv
module, which provides functions and classes for reading and writing CSV files. Here's an example of how to read a CSV file:
import csv
with open('data.csv', 'r') as file:
reader = csv.reader(file)
for row in reader:
print(row)
This code opens the data.csv
file, creates a csv.reader
object, and then iterates over each row in the file, printing the contents of each row.
CSV File Structure
A typical CSV file has the following structure:
header_row, header_row, header_row
data_row, data_row, data_row
data_row, data_row, data_row
The first row is usually the header row, which contains the names of the columns. The subsequent rows contain the actual data.
Handling Different Delimiters
By default, the csv
module in Python uses a comma (,
) as the delimiter. However, you can specify a different delimiter when reading or writing a CSV file:
import csv
with open('data.tsv', 'r') as file:
reader = csv.reader(file, delimiter='\t')
for row in reader:
print(row)
In this example, the CSV file is tab-separated (TSV), so we use '\t'
as the delimiter.
Conclusion
In this section, you've learned about the basics of CSV data in Python, including the structure of a CSV file, how to access CSV data using the csv
module, and how to handle different delimiters. This understanding will be crucial as you move on to handling missing or corrupted data in CSV files.