code: def _getOutputElegant(self, **kws):
          
          datascript = "sddsprintdata.sh"
          datapath = self.sim_path
          trajparam_list = kws['data']
          sddsfile = os.path.expanduser(os.path.join(self.sim_path, kws['file']))
          dh = datautils.DataExtracter(sddsfile, *trajparam_list)
          dh.setDataScript(datascript)
          dh.setDataPath(datapath)
          if 'dump' in kws:
              dh.setH5file(kws['dump'])
              dh.extractData().dump()
          data = dh.extractData().getH5Data()
          return data
docs: get results from elegant output according to the given keywords,
              input parameter format: key = sdds field name tuple, e.g.:
              available keywords are:
               - 'file': sdds fielname, file = test.sig
               - 'data': data array,    data = ('s','Sx')
               - 'dump': h5file name, if defined, dump data to hdf5 format