How to Declare a 2d Numpy Array in Python

This tutorial will provide insight into how to declare a 2D array in Python using Numpy, which is a powerful mathematical library that supports a wide range of arrays and matrices operations.

In Python, multidimensional arrays are important when performing operations on data. A 2D array has rows and columns, making it suitable to handle data that cannot be handled by 2D arrays.

Step 1: Install the Numpy package

First of all, install the Numpy package if it has not been installed yet. You can install it via pip:

Step 2: Import the Numpy library

Before we can declare a 2D Numpy array, we need to import the Numpy library:

Step 3: Declare a 2D Numpy Array

Now that we’ve imported Numpy, we can declare a 2D Numpy array. Arrays in Numpy can be created using the array() function:

In this code, we’re declaring a 2D Numpy array with the name “arr”. This array has 2 rows and 3 columns.

Full code

Code output

Let’s print out the output of this 2D numpy array:

[[1 2 3]
 [4 5 6]]

Conclusion

As you have seen, declaring a 2D Numpy array is quite simple. You only need to import the Numpy library, and then create your array using the array() function. Remember to place your data in nested brackets to create a 2D structure. While this tutorial covers creating arrays with manually specified values, Numpy also offers functions to generate arrays with random values, or other specific patterns. Check out more about these and other functionality in the Numpy documentation.