Run results for: Fill an MxN 2D nested array with random numbers

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36

Browser: Chrome 116

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Script Preparation code:

var M = 1000,
    N = 500;

AخA
 
var M = 1000,    N = 500;

Tests:

const arr = [];
for(let i = 0; i < M; i += 1) {
  arr[i] = [];
  for(let j = 0; j < N; j += 1)
    arr[i][j] = Math.random() * 2 - 1;
}
return arr;

 
const arr = [];for(let i = 0; i < M; i += 1) {  arr[i] = [];  for(let j = 0; j < N; j += 1)    arr[i][j] = Math.random() * 2 - 1;}return arr;

const arr = Array(M).fill(0).map(a => Array(N).fill(0).map(b => Math.random() * 2 - 1));
return arr;

 
const arr = Array(M).fill(0).map(a => Array(N).fill(0).map(b => Math.random() * 2 - 1));return arr;

const arr = Array.from({ length: M }, () => Array.from({ length: N }, () => Math.random() * 2 - 1));
return arr;

 
const arr = Array.from({ length: M }, () => Array.from({ length: N }, () => Math.random() * 2 - 1));return arr;

const arr = [...Array(M)].map(a => [...Array(N)].map(b => Math.random() * 2 - 1));

 
const arr = [...Array(M)].map(a => [...Array(N)].map(b => Math.random() * 2 - 1));