Object delete vs. array splice vs. array delete (v3)

Revision 3 of this benchmark created by Quentin Brooks on

Description

Is it faster to remove an item from an array (and thus allow the indices to be renumbered) or delete a property from an object. Also, checking deletion from array, but this does not renumber the indices so may not be preferable.

Preparation HTML

<script>
  var count = 100000;
  var deleteInc = 100;
</script>

Setup

var someArr = [];
      var someObj = {};
      for(var i = 0; i < count; i++)
      {
        someArr[i] = Math.floor(Math.random() * 1000000);
        someObj['a' + i] = Math.floor(Math.random() * 1000000);
      }

Test runner

Ready to run.

Testing in
TestOps/sec
Splice
for(var i = 0; i < count; i += deleteInc)
{
    someArr.splice(i, 1);
}
ready
Object Delete
for(var i = 0; i < count; i += deleteInc)
{
    delete someObj['a' + i];
}
ready
Array Delete
for(var i = 0; i < count; i += deleteInc)
{
    delete someArr[i];
}
ready
Object sub-script Delete
 
ready

Revisions

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