How to add characters in string in Python

We may occasionally run into situations where we need to add a certain character after the pair (second) of characters. This type of issue might arise when working with data that calls for the addition of special characters, such as commas or other symbols, particularly in the machine learning field. Let's talk about some approaches to solving this issue.

In Python, strings are immutable, which means once a string is created, its contents cannot be changed. However, you can create a new string by concatenating two or more strings. There are several ways to add characters to a string in Python, and in this article, we will explore some of the most commonly used methods.

Method #1: Combining list comprehension and join():

Specific work can be completed using a combination of the methods above. Slicing and list comprehension can be used to turn a string into a list, and the join function may be used to reconnect them while introducing the necessary characters.

Example:

Output:

The original string is :JavaTpoint

Explanation:

The string after inserting comma after every character pair: Ja,va,Tp,oi,nt. The time complexity of this method is O(n), where n is the length of the input string.

Method 2: Using the join() method

This specific task can be carried out using the combination of the aforementioned features. In this method, the split function is used to divide the odd and even characters, while the zip function turns the characters into iterable tuples. After that, the tuples are transformed into a list of strings through list comprehension, and the final result is joined using the join function.

The join() method is a powerful way to concatenate strings in Python. This method takes an iterable (such as a list or a tuple) of strings as input and concatenates them using the string on which it is called.

Example:

Let's take an example to understand this method:

Output:

Hello World

Explanation:

In this example, we have created a list of strings called string_list. After that, we used the join() method to concatenate the strings in the list with a space delimiter between them.

Method 3: Using formatted string literals

Formatted string literals are also known as f-strings. These are a more modern way to concatenate strings in Python. This method allows you to embed expressions inside string literals, which are then evaluated and replaced with their values at runtime. Here's an example:

Output:

My name is John and I am 30 years old.

Explanation:

In this example, we have created two variables, name and age, and used them inside a formatted string literal to create a new string. The expressions inside the curly braces are evaluated and replaced with their values at runtime.

Method 4: Using the += operator

Another way to add characters to a string is by using the += operator. This operator appends the new characters to the end of the existing string. Here's an example:

Output:

Hello World!

Explanation:

In this example, we have created a string string1 with the value "Hello". After that, we used the += operator to append the string " World!" to the end of string1.

Conclusion:

There are many ways to concatenate strings in Python, each with its own advantages and disadvantages. The + operator and the += operator are simple and easy to use, but they can be slow when concatenating large strings. The join() method is more efficient when concatenating large numbers of strings, but it requires more setup code. Formatted string literals are a more modern and powerful way to concatenate strings, but they may not be compatible with older versions of Python.