Python - Ways to invert mapping of dictionary

Dictionary is a collection which is unordered, changeable and indexed. In Python, dictionaries are written with curly brackets, and they have keys and values. It is widely used in day to day programming, web development, and machine learning.

Example

 Live Demo

# using dict comprehension
# initialising dictionary
ini_dict = {101: "vishesh", 201 : "laptop"}
# print initial dictionary
print("initial dictionary : ", str(ini_dict))
# inverse mapping using dict comprehension
inv_dict = {v: k for k, v in ini_dict.items()}
# print final dictionary
print("inverse mapped dictionary : ", str(inv_dict))
# using zip and dict functions
# initialising dictionary
ini_dict = {101: "vishesh", 201 : "laptop"}
# print initial dictionary
print("initial dictionary : ", str(ini_dict))
# inverse mapping using zip and dict functions
inv_dict = dict(zip(ini_dict.values(), ini_dict.keys()))
# print final dictionary
print("inverse mapped dictionary : ", str(inv_dict))
# using map and reversed
# initialising dictionary
ini_dict = {101: "akshat", 201 : "ball"}
# print initial dictionary
print("initial dictionary : ", str(ini_dict))
# inverse mapping using map and reversed
inv_dict = dict(map(reversed, ini_dict.items()))
# print final dictionary
print("inverse mapped dictionary : ", str(inv_dict))
# using lambda
# initialising dictionary
ini_dict = {101 : "akshat", 201 : "ball"}
# print initial dictionary
print("initial dictionary : ", str(ini_dict))
# inverse mapping using lambda
lambda ini_dict: {v:k for k, v in ini_dict.items()}
# print final dictionary
print("inverse mapped dictionary : ", str(ini_dict))

Output

('initial dictionary : ', "{201: 'laptop', 101: 'vishesh'}")
('inverse mapped dictionary : ', "{'laptop': 201, 'vishesh': 101}")
('initial dictionary : ', "{201: 'laptop', 101: 'vishesh'}")
('inverse mapped dictionary : ', "{'laptop': 201, 'vishesh': 101}")
('initial dictionary : ', "{201: 'ball', 101: 'akshat'}")
('inverse mapped dictionary : ', "{'ball': 201, 'akshat': 101}")
('initial dictionary : ', "{201: 'ball', 101: 'akshat'}")
('inverse mapped dictionary : ', "{201: 'ball', 101: 'akshat'}")

Nizamuddin Siddiqui

Published on 06-Aug-2020 14:21:55

• Related Questions & Answers
• Python – Mapping Matrix with Dictionary
• Python - Ways to Copy Dictionary
• Python – Cross mapping of Two dictionary value lists
• Python - Ways to create a dictionary of Lists
• Python - Ways to remove a key from dictionary
• Python Mapping Types
• Invert Binary Tree in Python
• Program to find number of ways to form a target string given a dictionary in Python
• Flip and Invert Matrix in Python
• Program to invert a binary tree in Python
• Convert string dictionary to dictionary in Python
• How to create Python dictionary from the value of another dictionary?
• How to convert Javascript dictionary to Python dictionary?
• How to define a Python dictionary within dictionary?
• Scatter plot and Color mapping in Python