code: def interpolate_ck2004_ldcoeffs(self, Teff=5772., logg=4.43, abun=0.0, atm='ck2004', ld_func='power', photon_weighted=False):
          
  
          if 'ck2004_ld' not in self.content:
              print('Castelli & Kurucz (2004) limb darkening coefficients are not computed yet. Please compute those first.')
              return None
  
          if photon_weighted:
              table = self._ck2004_ld_photon_grid
          else:
              table = self._ck2004_ld_energy_grid
  
          if not hasattr(Teff, '__iter__'):
              req = np.array(((Teff, logg, abun),))
              ld_coeffs = libphoebe.interp(req, self._ck2004_intensity_axes[0:3], table)[0]
          else:
              req = np.vstack((Teff, logg, abun)).T
              ld_coeffs = libphoebe.interp(req, self._ck2004_intensity_axes[0:3], table).T
  
          if ld_func == 'linear':
              return ld_coeffs[0:1]
          elif ld_func == 'logarithmic':
              return ld_coeffs[1:3]
          elif ld_func == 'square_root':
              return ld_coeffs[3:5]
          elif ld_func == 'quadratic':
              return ld_coeffs[5:7]
          elif ld_func == 'power':
              return ld_coeffs[7:11]
          elif ld_func == 'all':
              return ld_coeffs
          else:
              print('ld_func=%s is invalid; please choose from [linear, logarithmic, square_root, quadratic, power, all].')
              return None
docs: Interpolate the passband-stored table of LD model coefficients.