code: function(jd) {
  			jd = Math.floor(jd) + 0.5 - this.jdEpoch;
  			var year = Math.floor(jd / 360);
  			jd = jd % 360;
  			jd += (jd < 0 ? 360 : 0);
  			var month = Math.floor(jd / 20);
  			var day = jd % 20;
  			return this.newDate(year, month, day);
  		}
docs: Create a new date from a Julian date.
  @memberof MayanCalendar
  @param jd {number} The Julian date to convert.
  @return {CDate} The equivalent date.