Understanding Arrays in Python: Using Lists and External Libraries

Discover how to work with arrays in Python by using lists as arrays. This guide explains that while Python does not have built-in array support, you can utilize lists and external libraries like NumPy for array functionality. Learn how arrays help store multiple values in a single variable with practical examples.

Python Arrays

Note: Python does not have built-in support for Arrays, but Python Lists can be used instead.

Arrays

Note: This page shows you how to use LISTS as ARRAYS, however, to work with arrays in Python you will have to import a library, like the NumPy library.

Arrays are used to store multiple values in one single variable:

cars = ["Ford", "Volvo", "BMW"]

What is an Array?

An array is a special variable, which can hold more than one value at a time.

If you have a list of items (a list of car names, for example), storing the cars in single variables could look like this:

car1 = "Ford"
car2 = "Volvo"
car3 = "BMW"

However, what if you want to loop through the cars and find a specific one? And what if you had not 3 cars, but 300?

The solution is an array!

An array can hold many values under a single name, and you can access the values by referring to an index number.

Access the Elements of an Array

You refer to an array element by referring to the index number.

x = cars[0]

cars[0] = "Toyota"

The Length of an Array

Use the len() method to return the length of an array (the number of elements in an array).

x = len(cars)

Note: The length of an array is always one more than the highest array index.

Looping Array Elements

You can use the for loop to loop through all the elements of an array.

for x in cars:
print(x)

Adding Array Elements

You can use the append() method to add an element to an array.

cars.append("Honda")

Removing Array Elements

You can use the pop() method to remove an element from the array.

cars.pop(1)

You can also use the remove() method to remove an element from the array.

cars.remove("Volvo")

Note: The list's remove() method only removes the first occurrence of the specified value.

Array Methods

Python has a set of built-in methods that you can use on lists/arrays.