Math.round vs hack

JavaScript performance comparison

Revision 81 of this test case created by GoToLoop

Preparation code

<script>
  var num = -500 + (Math.random()*1000);
  var rounded;
</script>
    

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
"proper" rounding
rounded = Math.round(num);
pending…
Hack rounding
rounded = ~~(.5 + num);
pending…
Proper hack rounding
rounded = ~~(num + (num > 0? .5 : -.5));
pending…
Hack rounding 2
rounded = num+.5 | 0;
pending…

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Revisions

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