def extract_columns(rows, header)
      columns = []
      header.each do |h|
        columns << rows.map do |r|
          r.send(h)
        end  
      end
      columns
    end
def extract_columns(rows, header)
      columns = []
      header.each do |h|
        columns << rows.map do |r|
          r.send(h)
        end  
      end
      columns
    end
Extracts the columns to display in the table based on the header column
 names