Fastest JavaScript summation

Question

What is the fastest way to sum up an array in JavaScript? A quick search turns over a few different methods, but I would like a native solution if possible. This will run un

Answer 1

Improvements

Your looping structure could be made faster:

---

   var count = 0;
   for(var i=0, n=array.length; i < n; i++) 
   { 
      count += array[i]; 
   }

This retrieves array.length once, rather than with each iteration. The optimization is made by caching the value.

If you really want to speed it up:

---

   var count=0;
   for (var i=array.length; i--;) {
     count+=array[i];
   }

This is equivalent to a while reverse loop. It caches the value and is compared to 0, thus faster iteration.

For a more complete comparison list, see my JSFiddle.
Note: array.reduce is horrible there, but in Firebug Console it is fastest.

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Compare Structures

I started a JSPerf for array summations. It was quickly constructed and not guaranteed to be complete or accurate, but that's what edit is for :)