Create An Empty Javascript List

Michael Zippo 04.11.2021

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To initialize a list in Python, assign one with square brackets, initialize with the list () function, create an empty list with multiplication, or use a list comprehension. The most common way to declare a list in Python is to use square brackets.

A list is a data structure in Python that contains an ordered sequence of zero or more elements . Lists in Python are editable, which means they can be edited. They can contain any type of data, such as a string or a dictionary.

When you start working with lists you might ask yourself: how do I initialize a list in Python ? Or, in other words: how to create a Python list ?

This tutorial will answer that question and look at ways to initialize a list in Python. We’ll go over the basics of lists and how you can initialize a list using bracketed notation, list (), list multiplication, and understanding lists.

Updating the Python list

lists store zero or more items. Each element of a list is named element . Lists are often referred to as Python array .

In Python, the elements of a list are separated by commas and the list itself is surrounded by a square parenthesis. Here is an example of a list in Python:

Our list contains three values: Software Engineer, Web Developer and Data Analyst. We can reference our list using the "jobs" variable we declared above.

How to create a list in Python

You can initialize a list in Python using brackets, the list () method, multiplying lists and understanding lists.

The brackets allow you to initialize an empty list or a list that contains predefined values. The list () method works the same as square brackets. Although you need to add brackets and a list of items inside the list () method if you want to add some initial values.

List multiplication allows you to create a new list that repeats the elements of an existing list. Understanding Lists allows you to create a new list from the contents of an existing list.

Python Create List: brackets

You can use brackets or the () list method to initialize an empty list in Python. For the purposes of this tutorial, we’ll focus on how you can use square brackets or the list () method to initialize an empty list.

If you want to create an empty list list without values, you can declare your ad in two ways. First, you can declare a list with no values ‚Äã‚Äãby specifying a set of brackets with no component values. Here is an example of this syntax:

Our code returns: [].

Square brackets with nothing between them represent an empty list.

We can specify some default values ‚Äã‚Äãby appending them between our square brackets:

We have declared a list object with two initial values: "Software Engineer" and "Data Analyst".

Python Create List: list () method

Another way to create an empty list in Python with no values ‚Äã‚Äãis to use the list () method . Here is an example of the list () method in action:

Our code returns: [].

These first two approaches return the same answer: an empty list. There are no standards for when it is best to use one of these approaches. The empty square brackets ([]) approach is generally used because it is more concise.

Python Declare List: List Multiplication

One approach to initialize a list with multiple values ‚Äã‚Äãis list multiplication. This approach allows you to create a list with a number of predefined values.

So let’s say we create a program that asks us to name our top 10 favorite books. We want to initialize an array that will store the books that we insert. We could do this using the following code:

Our code returns:

Our program has created a list that contains 10 values.

Let’s break down our code. In the first line, we use the multiplication syntax to declare a list with 10 values. The value we use for each item in this list is "" or an empty string. Next, we use the Python print () function to print our list to the console.

We can use this syntax to initialize a list with whatever value we want. If we wanted our list to start with 10 values ‚Äã‚Äãequal to Choose a book., we could use the following code:

When we run our code, we create a list with 10 values. Each value in the list is equal to Choose a book.. We print this list on the console:

Python Declare List: List Understanding

In the previous section, we showed how to initialize a list using list multiplication. This approach is useful because it allows you to initialize a list with default values.

You can also initialize a list with default values ‚Äã‚Äãusing the list comprehension method. An Understanding Python List refers to a technique that allows you to create lists using an existing iterable object. The iterable object can be a list or an range () statement or some other type of iterable.

Understanding lists is a useful way to define an iterator-based list because it is elegant, simple, and broadly recognized.

Let’s say we want to create a list with 10 values ‚Äã‚Äãequal to Pick a book., as we did in the previous example. We could do this by understanding the lists using the following code:

In the example above, we are using list comprehension to create a list.The list comprehension statement is the iterator for i in range ( 10), used to create a list that repeats the value Choose a book ten times.

Conclusion

Initializing a list is a fundamental part of working with lists This tutorial explains how to initialize empty lists using square brackets and list () This is also shows how to use list multiplication and understand the techniques to create a list containing a number of values.

Read our How to learn Python for tips on learning more about the Python programming language.

We hope this article has helped you to resolve the problem. Apart from Create An Empty Javascript List, check other array Python module-related topics.