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CSV files can store data in a table format. The data is a simple text file, each line of data is called a record, and each line can be separated by commas.

This article will discuss different ways to write a list to CSV in Python.

csv.writer()Write a list to CSV using the method in Python

We start by importing csvthe module.

import csv

Suppose we write the following entries into a CSV file.

RollNo, Name, Subject
1, ABC, Economics
2, TUV, Arts
3, XYZ, Python

Now, the complete example code is as follows.

import csv

with open("students.csv", "w", newline="") as student_file:
    writer = csv.writer(student_file)
    writer.writerow(["RollNo", "Name", "Subject"])
    writer.writerow([1, "ABC", "Economics"])
    writer.writerow([2, "TUV", "Arts"])
    writer.writerow([3, "XYZ", "Python"])

If you run the code above, students.csva file will be created in the current directory with the entries in it as they appear in the code. csv.writer()The function will create writer()the object and writer.writerow()the command will insert the entries into the CSV file line by line.

Writing Lists to CSV Using Quotes in Python

In this method, we will see how to write quoted values ​​in CSV file. The complete sample code is as follows.

import csv

list = [["RN", "Name", "GRADES"], [1, "ABC", "A"], [2, "TUV", "B"], [3, "XYZ", "C"]]
with open("studentgrades.csv", "w", newline="") as file:
    writer = csv.writer(file, quoting=csv.QUOTE_ALL, delimiter=";")
    writer.writerows(list)

Creates a file in the current directory studentgrades.csv. csv.QUOTE_ALL()The function uses double quotes around all entries and ;separates them with the delimiter .

Output:

RN;"Name";"GRADES"
1;"ABC";"A"
2;"TUV";"B"
3;"XYZ";"C"

pandasWrite a list to CSV using the Python method

This method uses the Pandas library, which has a complete data frame. If you don’t have this library installed on your computer, you can use an online tool called Google Colab.

The complete example code is as follows.

import pandas as pd

name = ["ABC", "TUV", "XYZ", "PQR"]
degree = ["BBA", "MBA", "BSC", "MSC"]
score = [98, 90, 88, 95]
dict = {"name": name, "degree": degree, "score": score}
df = pd.DataFrame(dict)
df.to_csv("test.csv")

Output:

	name	degree	score
0	ABC	    BBA	     98
1	TUV	    MBA	     90
2	XYZ	    BSC	     88
3	PQR	    MSC	     95

This method writes a Python list to a CSV file as a data frame.

NumPyWrite a list to a CSV file using the method in Python

This method uses NumPythe library to save a list to a CSV file in Python. The complete example code is as follows.

import numpy as np

list_rows = [
    ["ABC", "COE", "2", "9.0"],
    ["TUV", "COE", "2", "9.1"],
    ["XYZ", "IT", "2", "9.3"],
    ["PQR", "SE", "1", "9.5"],
]
np.savetxt("numpy_test.csv", list_rows, delimiter=",", fmt="% s")

NumPyThe library's savetxt()function will write a CSV file from a Python list.

Output:

ABC	 COE	2	9
TUV	 COE	2	9.1
XYZ	 IT	2	9.3
PQR	 SE	1	9.5