docs: function decimalLength(n) {
  	let ns = cleanNumber(n).toString();
  	let ems = ns.match(/e([\+\-]\d+)$/);
  	let e = 0;
  	if (ems && ems[1]) e = parseInt(ems[1]);
  	ns = ns.replace(/e[\-\+]\d+$/, '');	
  	let parts = ns.split('.', 2);
  	if (parts.length === 1) return -e;
  	return parts[1].length - e;
  }