javascript double array 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: how to read 2 dimensional array in javascript

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

Example 3: 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 4: creating a 2d array in js

var x = new Array(10);

for (var i = 0; i < x.length; i++) {
  x[i] = new Array(3);
}

console.log(x);

Example 5: javascript two dimensional array

var grid = [];
iMax = 3;
jMax = 2;
count = 0;

    for (let i = 0; i < iMax; i++) {
      grid[i] = [];

      for (let j = 0; j < jMax; j++) {
        grid[i][j] = count;
        count++;
      }
    }

// grid = [
//   [ 0, 1 ]
//   [ 2, 3 ]
//   [ 4, 5 ]
// ];

console.log(grid[0][2]); // 4

Example 6: how to double array data in js

function double (arr){
    let newArr = [];
    for(let i = 0; i < arr.length; i++){
        newArr.push(arr[i] * 2);
    }
    console.log(newArr) ;
}
console.log(double([3,4,5]));