def text(str)
      if @xmlstack.last == :c
        if @cell.type != "shared" && @cell.type != "e" && str.numeric?
          @cell.v str
          @cellarray << @cell
        end
        @cell = Cell.new
      end
    end
def text(str)
      if @xmlstack.last == :c
        if @cell.type != "shared" && @cell.type != "e" && str.numeric?
          @cell.v str
          @cellarray << @cell
        end
        @cell = Cell.new
      end
    end
Cell content is parsed here. For cells containing strings, interpolation using the
 sharedStrings.xml file is done in the #Sharedstrings class.
 The numformat attribute gets a value here based on the styles variable, to preserve the numeric formatting (thus the type) of values.