sum with parallable

parallable.sum.js

var sum = parallable("sum.js", function (list) {
		if (this.shared !== undefined) {
			this.shared.list = list;
		}
		var pre = function (worker_num) {
			var list = this.shared.list;
			var part = new Array(worker_num);
			var i;
			var len = Math.ceil(list.length / worker_num);
			for (i = 0; i < worker_num; i++)
				part[i] = new Array(len);
			for (i = 0; i < list.length; i++)
				part[Math.floor(i / len)][i % len] = list[i];
			return part;
		};
		var core = function (data, id, worker_num) {
			var i, j;
			var sum = 0;
			for (i = 0; i < data.length; i++)
				for (j = 0; j < 5000; j++)
					sum += Math.cos(Math.sin(data[i]));
			return sum;
		};
		var post = function (seq) {
			var i;
			var sum = 0;
			for (i = 0; i < seq.length; i++)
				sum += seq[i];
			return sum;
		};
		return { "pre" : pre, "core" : core, "post" : post };
});