using Array.fill or from to create m by n array

Question

How to create a [m, n] sized array pre-filled with 0 in ES6

var x = Array.from(Array(5), () => 0)

gives a array of length 5. I need one with 5x3

var x = Array.from(Array(Array.from(Array(3),()=>0)), () => 0)

Oriol · Accepted Answer · 2016-06-13T10:11:56.767

3

Create an array with n zeros:

Array(n).fill(0)

Create an array which contains m times the same array with n zeros:

Array(m).fill(Array(n).fill(0));

Create an array which contains m different arrays with n zeros:

Array(m).fill().map(() => Array(n).fill(0));

Example:

console.log(JSON.stringify( Array(5).fill().map(() => Array(3).fill(0)) ));

edited Jun 13 '16 at 10:11

answered Jun 13 '16 at 10:06

Oriol

1

Also see [Most efficient way to create a zero filled JavaScript array?](http://stackoverflow.com/q/1295584/1529630) and [Array.prototype.fill() with object passes reference and not new instance](http://stackoverflow.com/q/35578478/1529630) – Oriol Jun 13 '16 at 10:28

score 2 · Answer 2 · answered Jun 13 '16 at 10:06

2

Your syntax is incorrect do it like

var x = Array.from(Array(5), () => Array.from(Array(3), () => 0));

console.log(x);

answered Jun 13 '16 at 10:06

Pranav C Balan

2 Answers2