code: def numeric_type(self, tchain, p_elem):
          
          typ = tchain[0].arg
          def gen_data():
              elem = SchemaNode("data").set_attr("type", self.datatype_map[typ])
              if typ == "decimal64":
                  fd = tchain[0].search_one("fraction-digits").arg
                  SchemaNode("param",elem,"19").set_attr("name","totalDigits")
                  SchemaNode("param",elem,fd).set_attr("name","fractionDigits")
              return elem
          self.type_with_ranges(tchain, p_elem, "range", gen_data)
docs: Handle numeric types.