def init_sum_scheme(sum_scheme)

        return if sum_scheme.nil?

        re = /(\w+):(\d+)|(\w+)/

        sum_scheme.scan(re).each do |part|
          if part.compact.size == 2
            @sum_row_title = part[0]
            @sum_row       = part[1].to_i
          else
            @sum_col_title = part[2]
          end
        end

      end
def init_sum_scheme(sum_scheme)

        return if sum_scheme.nil?

        re = /(\w+):(\d+)|(\w+)/

        sum_scheme.scan(re).each do |part|
          if part.compact.size == 2
            @sum_row_title = part[0]
            @sum_row       = part[1].to_i
          else
            @sum_col_title = part[2]
          end
        end

      end
Initializes the sum row title an positions as well as the sum column
 title