2 dimensional array javascript code example

Example 1: js array two dimensional

// declaration of a two-dimensional array
// 5 is the number of rows and 4 is the number of columns.
const matrix = new Array(5).fill(0).map(() => new Array(4).fill(0));

console.log(matrix[0][0]); // 0

Example 2: n dimensional array js

// function to create a n-dimentional array
function createArray(length) {
    var arr = new Array(length || 0),
        i = length;

    if (arguments.length > 1) {
        var args = Array.prototype.slice.call(arguments, 1);
        while(i--) arr[length-1 - i] = createArray.apply(this, args);
    }

    return arr;
}

//eg.
createArray();     // [] or new Array()

createArray(2);    // new Array(2)

createArray(3, 2); // [new Array(2),
                   //  new Array(2),
                   //  new Array(2)]

Example 3: how to read 2 dimensional array in javascript

activities.forEach((activity) => {
    activity.forEach((data) => {
        console.log(data);
    });
});

Example 4: javascript define multidimensional array

var iMax = 20;
var jMax = 10;
var f = new Array();

for (i=0;i<iMax;i++) {
 f[i]=new Array();
 for (j=0;j<jMax;j++) {
  f[i][j]=0;
 }
}

Example 5: javascript fill 2 dimensional array

const fillSquareMatrix = (size) => {
  return Array(size)
    .fill()
    .map((u,y) => Array(size)
         .fill()
         .map((u,x) => y * size + x + 1));
};

console.log(fillSquareMatrix(3));

Example 6: multi dimensional array javascript

//2D array
let activities = [
    ['Work', 9],
    ['Eat', 1],
    ['Commute', 2],
    ['Play Game', 1],
    ['Sleep', 7]
];