code: def force_balanced_LP(self):
          r
          dummy, xiA1, xiA2, xiA3, xiA4 = self.xiA
          self.xiA = np.array([1, xiA1, 0, xiA3, 0], dtype=np.float64)
          self.calc_ABDE_from_lamination_parameters()
docs: r"""Force balanced lamination parameters
  
          The lamination parameters `\xi_{A2}` and `\xi_{A4}` are set to null
          to force a balanced laminate.