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 under SpiderMonkey.

Thinking very inside-the-box I have been using:

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

I’m sure there is a better way then straight iteration.

Answer 1

You should be able to use reduce.

var sum = array.reduce(function(pv, cv) { return pv + cv; }, 0);

Source

And with arrow functions introduced in ES6, it’s even simpler:

sum = array.reduce((pv, cv) => pv + cv, 0);