# How to Create a Two Dimensional Array in JavaScript

The two-dimensional array is a set of items sharing the same name. The two-dimensional array is an array of arrays, that is to say, to create an array of one-dimensional array objects. They are arranged as a matrix in the form of rows and columns.

JavaScript suggests some methods of creating two-dimensional arrays.

## How to Create a Two-Dimensional Array?

To create a two-dimensional array in JavaScript, you can use an array of arrays. Here's an example:

``````var myArray = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9]
];``````

In this example, we have a two-dimensional array with three rows and three columns. Each row is an array containing three values.

To access an element in a two-dimensional array, you can use two sets of square brackets. The first set of brackets specifies the row, and the second set of brackets specifies the column. For example:

How to Create a Two-Dimensional Array in JavaScript?
var myArray = [ [1, 2, 3], [4, 5, 6], [7, 8, 9] ]; var element = myArray[1][2]; // gets the value in the second row, third column (6) console.log(element)

In this example, we've accessed the element in the second row and third column of the array (with indices 1 and 2, respectively), which has a value of 6.

You can also use loops to iterate over the elements in a two-dimensional array. For example:

Example of iterating over the elements in a two-dimensional array in JavaScript
var myArray = [ [1, 2, 3], [4, 5, 6], [7, 8, 9] ]; for (var i = 0; i < myArray.length; i++) { for (var j = 0; j < myArray[i].length; j++) { console.log(myArray[i][j]); // prints each element in the array } }

## Array Constructor

You can use the array constructor and the for loop to create a 2D array like this:

Javascript array constructor
const m = 4; const n = 5; let arr = new Array(m); // create an empty array of length n for (var i = 0; i < m; i++) { arr[i] = new Array(n); // make each element an array } console.log(arr); // Output: [ [ <5 empty items> ], [ <5 empty items> ], [ <5 empty items> ], [ <5 empty items> ] ]

In this example, we've used two nested loops to iterate over each element in the array and print its value to the console.

## Array Literal Notation

Lieteral notation method can also be used to create 2D arrays:

Javascript array literal notation
const m = 4; const n = 5; // Note 2nd dimention is not relevant here let arr = []; for (var i = 0; i < m; i++) { arr[i] = []; } console.log(arr); // Output: [ [], [], [], [] ]

## The Array.from() method

The Array.from() method will return an array object from any JavaScript object with the length property or an iterable object.

Javascript array literal notation
const m = 4; const n = 5; let arr = Array.from(Array(m), () => new Array(n)); console.log(arr); // Output: [ [ <5 empty items> ], [ <5 empty items> ], [ <5 empty items> ], [ <5 empty items> ] ]

## The Array.prototype.map()Method

You can also call the map() function directly:

How to Create a Two Dimensional Array in JavaScript
const m = 4; const n = 5; let arr = Array(m).fill().map(() => Array(n)); console.log(arr); // Output: [ [ <5 empty items> ], [ <5 empty items> ], [ <5 empty items> ], , [ <5 empty items> ] ]

## Multidimensional Arrays

Multidimensional arrays are known in JavaScript as arrays inside another array as they are created by using another one-dimensional array.

They can have more than two dimensions. A two-dimensional array is also called a matrix or a table of rows and columns.