code: def same_branch_splines(self, convert_to_muC_per_cm2=True, all_in_polar=True):
          
          from scipy.interpolate import UnivariateSpline
          tot = self.get_same_branch_polarization_data(
              convert_to_muC_per_cm2=convert_to_muC_per_cm2, all_in_polar=all_in_polar)
          L = tot.shape[0]
          try:
              sp_a = UnivariateSpline(range(L), tot[:, 0].ravel())
          except:
              sp_a = None
          try:
              sp_b = UnivariateSpline(range(L), tot[:, 1].ravel())
          except:
              sp_b = None
          try:
              sp_c = UnivariateSpline(range(L), tot[:, 2].ravel())
          except:
              sp_c = None
          return sp_a, sp_b, sp_c
docs: Fit splines to same branch polarization. This is used to assess any jumps
          in the same branch polarizaiton.