Introduction Python String Maketrans() Method with Example

Introduction Python String Maketrans() Method with Example

Python string maketrans() is an inbuilt mapping function that maps the characters of a string to its replacement or, in other words, its translation. The maketrans() is a helper method for the translate() method...

Python string maketrans() is an inbuilt mapping function that maps the characters of a string to its replacement or, in other words, its translation. The maketrans() is a helper method for the translate() method. It helps the translate method by returning a translation table that is used for one to one mapping of string characters. It specifies the list of characters that are needed to be replaced from the main string or to be deleted.

Python String maketrans()

In simple terms, the maketrans() method is a static method that creates a one to one mapping of a character to its translation/replacement.

It creates a Unicode representation of each character for translation.

This translation mapping is then used for replacing a character to its mapped character when used in translate() method.

The syntax of maketrans() method is:

string.maketrans(x[, y[, z]])


Here, y and z are optional arguments.

String maketrans() Parameters

The maketrans() method takes 3 parameters:

  • x - If only one argument is supplied, it must be a dictionary.
    The dictionary should contain 1-to-1 mapping from a single character string to its translation OR a unicode number (97 for 'a') to its translation.

  • y - If two arguments are passed, it must be two strings with equal length.
    Each character in the first string is a replacement to its corresponding index in the second string.

  • z - If three arguments are passed, each character in the third argument is mapped to None.

Return value from String maketrans()

The maketrans() method returns a translation table with a 1-to-1 mapping of a Unicode ordinal to its translation/replacement.

Example program using maketrans() method in python

Example 1: Translation table using a dictionary with maketrans()

# example dictionary
dict = {"a": "123", "b": "456", "c": "789"}
string = "abc"
print(string.maketrans(dict))

# example dictionary
dict = {97: "123", 98: "456", 99: "789"}
string = "abc"
print(string.maketrans(dict))

When you run the program, the output will be:

{97: '123', 98: '456', 99: '789'}
{97: '123', 98: '456', 99: '789'}

Here, a dictionary dict is defined. It contains a mapping of characters a,b and c to 123, 456 and 789 respectively.

maketrans() creates a mapping of the character's Unicode ordinal to its corresponding translation.

So, 97 ('a') is mapped to '123', 98 'b' to 456 and 99 'c' to 789. This can be demonstrated from the output of both dictionaries.

Also, if two or more characters are mapped in the dictionary, it raises an exception.

Example 2: Translation table using two strings with maketrans()

# first string
firstString = "abc"
secondString = "def"
string = "abc"
print(string.maketrans(firstString, secondString))

# example dictionary
firstString = "abc"
secondString = "defghi"
string = "abc"
print(string.maketrans(firstString, secondString))

When you run the program, the output will be:


{97: 100, 98: 101, 99: 102}
ValueError: the first two maketrans arguments must have equal length

Here first, two strings of equal length "abc" and "def" are defined. And the corresponding translation is created.

Printing only the first translation gives you a 1-to-1 mapping to each character's Unicode ordinal in firstString to the same indexed character on the secondString.

In this case, 97 ('a') is mapped to 100 ('d'), 98 ('b') to 101 ('e') and 99 ('c') to 102 ('f').

Trying to create a translation table for unequal length strings raises a ValueError exception indicating that the strings must have equal length.

Learn More

Thanks for reading !

Top Python Development Companies | Hire Python Developers

Top Python Development Companies | Hire Python Developers

After analyzing clients and market requirements, TopDevelopers has come up with the list of the best Python service providers. These top-rated Python developers are widely appreciated for their professionalism in handling diverse projects. When...

After analyzing clients and market requirements, TopDevelopers has come up with the list of the best Python service providers. These top-rated Python developers are widely appreciated for their professionalism in handling diverse projects. When you look for the developer in hurry you may forget to take note of review and ratings of the company's aspects, but we at TopDevelopers have done a clear analysis of these top reviewed Python development companies listed here and have picked the best ones for you.

List of Best Python Web Development Companies & Expert Python Programmers.

Python GUI Programming Projects using Tkinter and Python 3

Python GUI Programming Projects using Tkinter and Python 3

Python GUI Programming Projects using Tkinter and Python 3

Description
Learn Hands-On Python Programming By Creating Projects, GUIs and Graphics

Python is a dynamic modern object -oriented programming language
It is easy to learn and can be used to do a lot of things both big and small
Python is what is referred to as a high level language
Python is used in the industry for things like embedded software, web development, desktop applications, and even mobile apps!
SQL-Lite allows your applications to become even more powerful by storing, retrieving, and filtering through large data sets easily
If you want to learn to code, Python GUIs are the best way to start!

I designed this programming course to be easily understood by absolute beginners and young people. We start with basic Python programming concepts. Reinforce the same by developing Project and GUIs.

Why Python?

The Python coding language integrates well with other platforms – and runs on virtually all modern devices. If you’re new to coding, you can easily learn the basics in this fast and powerful coding environment. If you have experience with other computer languages, you’ll find Python simple and straightforward. This OSI-approved open-source language allows free use and distribution – even commercial distribution.

When and how do I start a career as a Python programmer?

In an independent third party survey, it has been revealed that the Python programming language is currently the most popular language for data scientists worldwide. This claim is substantiated by the Institute of Electrical and Electronic Engineers, which tracks programming languages by popularity. According to them, Python is the second most popular programming language this year for development on the web after Java.

Python Job Profiles
Software Engineer
Research Analyst
Data Analyst
Data Scientist
Software Developer
Python Salary

The median total pay for Python jobs in California, United States is $74,410, for a professional with one year of experience
Below are graphs depicting average Python salary by city
The first chart depicts average salary for a Python professional with one year of experience and the second chart depicts the average salaries by years of experience
Who Uses Python?

This course gives you a solid set of skills in one of today’s top programming languages. Today’s biggest companies (and smartest startups) use Python, including Google, Facebook, Instagram, Amazon, IBM, and NASA. Python is increasingly being used for scientific computations and data analysis
Take this course today and learn the skills you need to rub shoulders with today’s tech industry giants. Have fun, create and control intriguing and interactive Python GUIs, and enjoy a bright future! Best of Luck
Who is the target audience?

Anyone who wants to learn to code
For Complete Programming Beginners
For People New to Python
This course was designed for students with little to no programming experience
People interested in building Projects
Anyone looking to start with Python GUI development
Basic knowledge
Access to a computer
Download Python (FREE)
Should have an interest in programming
Interest in learning Python programming
Install Python 3.6 on your computer
What will you learn
Build Python Graphical User Interfaces(GUI) with Tkinter
Be able to use the in-built Python modules for their own projects
Use programming fundamentals to build a calculator
Use advanced Python concepts to code
Build Your GUI in Python programming
Use programming fundamentals to build a Project
Signup Login & Registration Programs
Quizzes
Assignments
Job Interview Preparation Questions
& Much More

Guide to Python Programming Language

Guide to Python Programming Language

Guide to Python Programming Language

Description
The course will lead you from beginning level to advance in Python Programming Language. You do not need any prior knowledge on Python or any programming language or even programming to join the course and become an expert on the topic.

The course is begin continuously developing by adding lectures regularly.

Please see the Promo and free sample video to get to know more.

Hope you will enjoy it.

Basic knowledge
An Enthusiast Mind
A Computer
Basic Knowledge To Use Computer
Internet Connection
What will you learn
Will Be Expert On Python Programming Language
Build Application On Python Programming Language