How to create a pandas DataFrame?

by | Nov 9, 2022 | Machine Learning Using Python, Python Pandas

Pandas is an open-source Python library. It provides us with some new data structures, such as Series and DataFrame. A pandas Series is a one-dimensional data structure. It is similar to NumPy one-dimensional array or a Python list. But, the main difference is it is labeled. And the pandas DataFrame is a two-dimensional data structure. It can contain tabular data. In this article, we will discuss how to create a Pandas DataFrame.

We can use the pandas.DataFrame() constructor to create a pandas DataFrame.

import pandas

list1 = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
df1 = pandas.DataFrame(list1)
print(df1)

df2 = pandas.DataFrame(list1, index=["Row 1", "Row 2", "Row 3"], columns=["Column 1", "Column 2", "Column 3"])
print(df2)

dict1 = {“Column 1”: [1, 2, 3], "Column 2": [4, 5, 6], "Column 3": [7, 8, 9]}
df3 = pandas.DataFrame(dict1)
print(df3)

Here, list1 is a Python list that has three rows and three columns. We are using this list to create a DataFrame df1. So, df1 contains three rows and three columns. When we print df1, it shows the following:

   0  1  2
0  1  2  3
1  4  5  6
2  7  8  9

Please note that pandas DataFrame is a …

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Amrita Mitra

Author

Ms. Amrita Mitra is an author, who has authored the books “Cryptography And Public Key Infrastructure“, “Web Application Vulnerabilities And Prevention“, “A Guide To Cyber Security” and “Phishing: Detection, Analysis And Prevention“. She is also the founder of Asigosec Technologies, the company that owns The Security Buddy.

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