Zero Padding Numbers

JavaScript performance comparison

Test case created by Brandon Tilley


Testing multiple methods in which you can pad a number with zeros until the string reaches a predetermined length.

Preparation code

Benchmark.prototype.setup = function() {
    function padWhile(num, size) {
      var s = num+"";
      while (s.length < size) s = "0" + s;
      return s;
    function padJoin(num, places) {
      var zero = places - num.toString().length + 1;
      return Array(+(zero > 0 && zero)).join("0") + num;

Test runner

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Testing in unknown unknown
Test Ops/sec
Pad using While Loop
padWhile(5, 2);
padWhile(5, 4);
padWhile(502, 6);
padWhile(1234, 2);
Pad using Array#join
padJoin(5, 2);
padJoin(5, 4);
padJoin(502, 6);
padJoin(1234, 2);

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