1// declaration of a two-dimensional array
2// 5 is the number of rows and 4 is the number of columns.
3const matrix = new Array(5).fill(0).map(() => new Array(4).fill(0));
4
5console.log(matrix[0][0]); // 0
6

1
2        
3            
4        
5     activities.forEach((activity) => {
6    activity.forEach((data) => {
7        console.log(data);
8    });
9});

1/*having the previous array easy to make is very useful*/
2
3function Array2D(x, y){
4 let arr = Array(x);
5  for(let i = 0; i < y; i++){
6   arr[i] = Array(y);
7  }
8  return arr;
9}
10
11function Array3D(x, y, z){
12 let arr = Array2D(x, y);
13      for(let i = 0; i < y; i++){
14       for(let j = 0; j < z; j++){
15        arr[i][j] = Array(z);
16       }
17      }
18  return arr;
19}
20
21function Array4D(x, y, z, w){
22 let arr = Array3D(x, y, z);
23      for(let i = 0; i < x; i++){
24       for(let j = 0; j < y; j++){
25        for(let n = 0; n < z; n++){
26        arr[i][j][n] = Array(w);
27       }
28       }
29      }
30  return arr;
31}
32/*making the array*/
33let myArray = Array4D(10, 10, 10, 10);

1// function to create a n-dimentional array
2function createArray(length) {
3    var arr = new Array(length || 0),
4        i = length;
5
6    if (arguments.length > 1) {
7        var args = Array.prototype.slice.call(arguments, 1);
8        while(i--) arr[length-1 - i] = createArray.apply(this, args);
9    }
10
11    return arr;
12}
13
14//eg.
15createArray();     // [] or new Array()
16
17createArray(2);    // new Array(2)
18
19createArray(3, 2); // [new Array(2),
20                   //  new Array(2),
21                   //  new Array(2)]

1var iMax = 20;
2var jMax = 10;
3var f = new Array();
4
5for (i=0;i<iMax;i++) {
6 f[i]=new Array();
7 for (j=0;j<jMax;j++) {
8  f[i][j]=0;
9 }
10}
11

1//2D array
2let activities = [
3    ['Work', 9],
4    ['Eat', 1],
5    ['Commute', 2],
6    ['Play Game', 1],
7    ['Sleep', 7]
8];