code: def to_cr(self):
          
          data_new = self.data.copy()
          data_new['rpha'] = -1.5 * data_new['chargeability']
          # now that we have magnitude and phase, compute the impedance Zt
          data_new['Zt'] = data_new['r'] * np.exp(data_new['rpha'] * 1j / 1000.0)
          cr = reda.CR(data=data_new)
          return cr
docs: Convert container to a complex resistivity container, using the
          CPA-conversion.
  
          Kemna, 2000
  
          COMPLEX RESISTIVITY COPPER MlNERALlZATlONt SPECTRA OF PORPHYRY
          Van Voorhis, G. D.; Nelson, P. H.; Drake, T. L.
          Geophysics (1973 Jan 1) 38 (1): 49-60.
  
          Application of complex resistivity tomography to field data from
          a kerosene-contaminated siteGold Open Access Authors: A. Kemna, E.
          Räkers and A. Binley DOI: 10.3997/2214-4609.201407300
  
          Gianluca Fiandaca, Esben Auken, Anders Vest Christiansen, and
          Aurélie Gazoty (2012). ”Time-domain-induced polarization:
          Full-decay forward modeling and 1D laterally constrained inversion
          of Cole-Cole parameters.” GEOPHYSICS, 77(3), E213-E225.
          https://doi.org/10.1190/geo2011-0217.1