Run results for: Array initialization

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36

Browser: Chrome 55

Operating system: Windows 7

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
Decide length in `new`	84.0 Ops/sec
Decide length with assignment	12.8 Ops/sec
Push items separately	39.1 Ops/sec

Script Preparation code:

var len = 100;

Tests:

Decide length in `new`
var a = new Array(len), i; for (i = 0; i < len; i++) { a[i] = i; } window.a = a;
Decide length with .length
var a = [], i; a.length = len; for (i = 0; i < len; i++) { a[i] = i; } window.a = a;
Push items separately
var a = [], i; for (i = 0; i < len; i++) { a.push(i); } window.a = a;
Assign items separately
var a = [], i; for (i = 0; i < len; i++) { a[i] = i; } window.a = a;