How to reset the indexes of rows and columns of a DataFrame?

by | Nov 12, 2022 | Machine Learning Using Python, Python Pandas

rows.

import pandas

list1 = [[1, 2, 3, 4, 5], [6, 7, 8, 9, 10], [11, 12, 13, 14, 15], [16, 17, 18, 19, 20]]
df1 = pandas.DataFrame(list1)
print("df1: \n", df1)

df1.drop([0, 2], axis=0, inplace=True)
df1.drop([1, 2], axis=1, inplace=True)
print("df1 after dropping rows and columns: \n", df1)

df1.reset_index(drop=True, inplace=True)
print("df1 after resetting indexes of rows: \n", df1)

Here, the parameter drop=True indicates that the old indexes won’t be stored in the DataFrame as a new column. Instead, the old indexes will be dropped completely. And the parameter inplace=True indicates that we are not creating any new DataFrame after resetting the indexes of the rows.

The output of the above program will be:

df1: 
    0   1   2   3   4
0   1   2   3   4   5
1   6   7   8   9  10
2  11  12  13  14  15
3  16  17  18  19  20
df1 after dropping rows and columns: 
    0   3   4
1   6   9  10
3  16  19  20
df1 after resetting indexes of rows: 
    0   3   4
0   6   9  10
1  16  19  20

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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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