# File lib/numru/nusdas.rb, line 1142
    def dim(dname)
      if Integer === dname
        dname = dim_names[dname]
      elsif String === dname
        unless dim_names.include?(dname)
          raise "#{dname} does not exist"
        end
      else
        raise "argument is invalide"
      end
      return NuSDaSDim.new(dname, @meta, @type1[6,2])
    end