code: function (n) {
  		if (typeof(n) === 'undefined' || isNaN(n)) {
  			return [];
  		}
  		if (typeof ArrayBuffer === 'undefined') {
  			// lacking browser support
  			var arr = new Array(n);
  			for (var i = 0; i < n; i++) {
  				arr[i] = 0;
  			}
  			return arr;
  		} else {
  			return new Float64Array(n); // typed arrays are faster
  		}
  	}
docs: utilitity that creates contiguous vector of zeros of size n