code: function fixAngleOverlap(list) {
      var firstItem = list[0];
      var lastItem = list[list.length - 1];
      if (firstItem
          && lastItem
          && Math.abs(Math.abs(firstItem.coord - lastItem.coord) - 360) < 1e-4
      ) {
          list.pop();
      }
  }
docs: Remove the last tick which will overlap the first tick