code: func (cfe *CoordinatesFlatElement) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
  	if err := e.EncodeToken(coordinatesStartElement); err != nil {
  		return err
  	}
  	for i := cfe.offset; i < cfe.end; i += cfe.stride {
  		s := ""
  		if i != cfe.offset {
  			s = " "
  		}
  		s += strconv.FormatFloat(cfe.flatCoords[i], 'f', -1, 64) + "," + strconv.FormatFloat(cfe.flatCoords[i+1], 'f', -1, 64)
  		if cfe.dim > 2 && cfe.flatCoords[i+2] != 0 {
  			s += "," + strconv.FormatFloat(cfe.flatCoords[i+2], 'f', -1, 64)
  		}
  		if err := e.EncodeToken(xml.CharData([]byte(s))); err != nil {
  			return err
  		}
  	}
  	return e.EncodeToken(coordinatesEndElement)
  }
docs: // MarshalXML marshals cfe to e. start is ignored.