def rotate_horizontal
      return unless rotated?
      head, body = orientation.slice(self)
      if header && header.empty?
        @header = head[0]
        @rows   = body.map { |row| to_row(row, @header) }
      else
        @rows = body.map { |row| to_row(row) }
      end
    end
def rotate_horizontal
      return unless rotated?
      head, body = orientation.slice(self)
      if header && header.empty?
        @header = head[0]
        @rows   = body.map { |row| to_row(row, @header) }
      else
        @rows = body.map { |row| to_row(row) }
      end
    end
Rotate the table horizontally

 @api private