List append() Method in Python: All You Need To Know
Introduction
While working on one of the client’s projects, the developer is working on a program to create the code to keep a record of all the items in a basket. In that project, Project Manager decided to use the Python programming language due to its object-oriented and functional programming nature. Suddenly, the developer realizes that he has to find a way through which they can add items to that basket as he goes along. Eventually, after a lot of research on this task, they discovered one of the most popular methods used in python to do this task. The name of that method is the append() method from one of the classes of python, named list. With this method’s help, anyone can easily add an item to the end of a list object. which makes that list perfect for his basket list program.
Excited about this discovery, he started experimenting with the append() method and found that he could add individual items and entire lists to the main list. This made his program much more efficient and streamlined.
In this article or Python tutorial, we will dive deep into the append() method and explore some of the important features and uses of this method. This article caters to both beginners as well as experienced developers. So let’s get started and take a closer look at the append() method in Python!
Table of Contents
List Collection Type
In Python, one of the most common and useful data types is a list, which is basically a collection data type that allows storing a collection of items in a single variable. This is similar to arrays, but the main difference is that array can only store elements of the same data type, whereas List can also store heterogeneous elements.
Properties of List Collection Type in Python
The main properties of this data type are as follows:
- Lists are ordered, changeable, and allow duplicate values.
- They are incredibly versatile and can be used in various programming applications.
Now, one of the important methods of this very big collection is the append() method, and now let’s start to discuss the role of that method.
To understand the List methods, refer to one of the beginner-level articles from Analytics Vidhya.
Role of the Python List Append Method
- It is a built-in function that is used to add an item to the end of a list.
- It is a common and powerful method for modifying lists in terms of elements and updating the same variable itself.
- It allows you to easily add new elements to a list without creating a new list each time.
Advantage of the Append Method
One of the main advantages of this method, which we can directly find from its implementation, is that it allows you to build lists in a dynamic fashion instead of a static one, which helps us to add the items to the list, which is particularly useful when we don’t know how many items we have to add to the list in advance.
Overall, the append() method is an essential tool for working with lists in Python, and mastering it will help you become a more efficient and effective programmer.
Append Method in Python
In Python, the append() method is a built-in function used to add an item to the end of a list.
The append() method is a member of the list object, and it is used to modify the contents of an existing list by adding a new element to the end of the list. The append () method returns nothing.
With the help of this method, we have to provide a simple function call to an existing list object and pass in the new item, which we have to add to the end of the list as an argument.
Every time we call this method on any existing list, this method adds a new item to the end of the list. You can refer to the link to learn more about the append method.
Syntax of the append() Method
The append() method appends an element to the end of the list.
Syntax:
list.append(element_to_be_added)The parameter used in this method is shown below:
Parameter: element_to_be_added
Description: This parameter is required for this method which may be an element of any data type (string, integer, float, object, etc.)
Therefore, we can see that this method takes a single argument, basically the item we must add to the end of the list. When we call this method on a list, the item we have specified is added to the end of the list, and as a result, the length of the list is increased by one.
Top 10 Examples of Append Method in Python
Now, let’s see how we can use this append method as iterables or iterators to do the following functionalities. For all of the below examples, we are using Python3, which is mostly used in technologies such as
- Data Science,
- Machine Learning,
- Deep learning, etc.
Similar kinds of working of these methods can be implemented in other programming languages such as Java, JavaScript, etc. Some of the Python Libraries are
- Numpy for Matrix Manipulations,
- Pandas for Data Analysis using Pandas DataFrame,
- Matplotlib for Data Visualisation,
- Tensorflow for Computer Vision,
- NLTK for Natural Language Processing, etc.
Example 1: Pushing a Single Item to a List
In this example, you can see that we have a list of fruits, and we are trying to add a new fruit (which means only a single element to be added) to the existing list, increasing the original list’s length by one. This method doesn’t have anything related to the return value.
# Created a list
fruits = ["grapes", "banana", "cherry", "orange"]
# Add a new element to the list of the above fruits
fruits.append("apple")
# Print the updated list
print(fruits)The output of the above program is shown below:
["grapes", "banana", "cherry", "orange", "apple"]Example 2: Pushing Multiple Items to a List Using a For Loop
In this example, you can see that we have a list of fruits, and we are trying to add some new fruits to the existing list, increasing the list’s length by the length of the new list. Also, the list is created with the help of square brackets, or we can also create it through list comprehension.
# Created a list
fruits = ["apple", "banana", "cherry"]
# Created a new list of fruits name
new_fruits = ["orange", "kiwi", "grape"]
# Looping over the list using For Loop to add elements
for fruit in new_fruits:
fruits.append(fruit)
# Print the updated list
print(fruits)The output of the above program is shown below:
["apple", "banana", "cherry", "orange", "kiwi", "grape"]Example 3: Pushing a List to Another List
In this example, you can see that we have a list of integers, and we are trying to add a new integer list to the existing list, increasing the list’s length and creating a nested list. This means we are doing list concatenation.
# Created a list
list1 = [1, 2, 3, 4, 5]
# Created a list
list2 = [4, 5, 6, 7, 8]
# Apply append function
list1.append(list2)
# Print the updated list
print(list1)The output of the above program is shown below:
[1, 2, 3, 4, 5, [4, 5, 6, 7, 8]]
Example 4: Pushing a List to Another List Using the extend() Method
As in the previous example, while using the append function, we have observed that due to the append() method, we are able to add the new list completely, but not in a separate manner, i.e., each element-wise, so to implements that tasks, In this example, we have taken a list of fruits.
We are trying to add a new integer list to the existing list, increasing the list length we have to add. (list.extend)
# Created a list
list1 = [1, 2, 3, 9, 10]
# Created a list
list2 = [4, 5, 6, 1, 8]
# Apply to extend function instead of append
list1.extend(list2)
# Print the updated list
print(list1)The output of the above program is shown below:
[1, 2, 3, 9, 10, 4, 5, 6, 1, 8]Example 5: Pushing a Python Tuple to a List
In this example, you can see that we have a list of fruits and are trying to add a new fruit tuples data storage in the existing list. We can easily observe that inside the list other than string, we have tuples of string that can easily be added at the end of the list.
# Created a list
fruits = ["apple", "banana", "cherry"]
# Created a Tuple
my_tuple = ("orange", "kiwi", "grape")
# Apply append function
fruits.append(my_tuple)
# Print the updated list
print(fruits)The output of the above program is shown below:
["apple", "banana", "cherry", ("orange", "kiwi", "grape")]Example 6: Pushing a Python Dictionary to a List
In the previous example, we add the tuple to an existing list. Still, in this, we will add one dictionary corresponding to the key value type of data structure, and the operation can be easily done. Also, observe that there are different types of elements according to the data type in the list. The indicated list can be heterogeneous, which means it can store elements of different data types.
# Created a list
fruits = ["apple", "banana", "cherry"]
# Created a Dictionary to add
my_dict = {"orange": 1, "kiwi": 2, "grape": 3}
# Apply append function
fruits.append(my_dict)
# Print the updated list
print(fruits)The output of the above program is shown below:
["apple", "banana", "cherry", {"orange": 1, "kiwi": 2, "grape": 3}]Example 7: Pushing an Integer to a List
In this example, you can see that we have a list of integers, and we are trying to add a new integer in the existing list, increasing the list’s length by one.
# Created a list
numbers = [1, 2, 3]
# Apply append function
numbers.append(4)
# Print the updated list
print(numbers)The output of the above program is shown below:
[1, 2, 3, 4]Example 8: Pushing a Python String to a List
In this example, you can see that we have a list of names of people, and we are trying to add a new person’s name to the existing list, increasing the list’s length by one. Only the thing is that the element which we have to add here is the string data type.
# Created a list
names = ["Alice", "Bob", "Charlie"]
# Apply append function
names.append("David")
# Print the updated list
print(names)The output of the above program is shown below:
["Alice", "Bob", "Charlie", "David"]Example 9: Pushing a Python Boolean to a List
In this example, you can see that we have a list of booleans, and we are trying to add a new boolean value to the existing list, increasing the list’s length by one. Only the thing is that the element we have to add here is the boolean data type means the value is either True or False.
# Created a list
flags = [True, False]
# Apply append function
flags.append(True)
# Print the updated list
print(flags)The output of the above program is shown below:
[True, False, True]Example 10: Pushing a None Value to a List
In this example, you can see that we have a list of integers, and we are trying to add a None value to the existing list, increasing the list’s length by one. Only the thing is that the element we have to add here is the None data type which means nothing.
# Created a list
values = [1, 2, 3]
# Apply append function
values.append(None)
# Print the updated list
print(values)The output of the above program is shown below:
[1, 2, 3, None]These examples demonstrate the versatility and power of the append() method in Python and show how it can be used to add a wide range of items to lists differently.
Conclusion
In conclusion, we can say that the append() method in Python programming language is a very powerful tool for adding new elements to an existing list. As we’ve observed in this article, it’s incredibly easy to use and can be used in a variety of different situations. Whether you’re working with a small or large list, the append() method can help you quickly add new items to your collection.
To illustrate the power of the append() method, we have discussed one of the stories. We can easily append the new items to the list by writing a few program lines.
- Regarding space complexity, we don’t have to create a new structure to store the updated list; we can utilize the initial list. In this way, we can say that this method is memory efficient.
- Also, we can add any data type to an existing list, which means the list can work for elements of the different data types.
Therefore, this append() method in Python is an essential tool that can help you quickly and easily add new elements to your list. Overall, the append() method is a powerful and essential tool for working with lists in Python, and it is used extensively in many different programming applications.
If you want to learn similar kind of concepts of Python, you can refer to the link:
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You can refer to the below link to find blog posts in which frequently asked questions related to the append() Method in Python are present:
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Frequently Asked Questions
Q1. Is Append a python built-in function?
A. Yes, append() is a built-in method in Python that belongs to the list collection type or class. This is used to add an item to the end of a list.
Q2. What is the difference between Append and Concat?
A. The append function will add new elements in the existing list iteratively one by one. In contrast, the Concat function will do a single operation to finish the job, i.e., directly add those elements in one iteration, which makes it faster than append().
Q3. What is the opposite of Append in python?
A. The opposite of append in Python is list. pop(index) removes and returns the element at the given index. Basically, this returns the rightmost element if the index is omitted, which can be considered roughly the opposite of append().
Q4. What is the python Append function used for?
A. It is a built-in function that adds an item to the end of a list. It is a common and powerful method for modifying lists in terms of elements and updating the same variable itself. It allows you to easily add new elements to a list without creating a new list each time.
Q5. Is Append the same as += in python?
A. The append() method adds elements to the list by utilizing a mutator() method, whereas the ‘+’ operator creates a new list with the capacity for one more element.
