code: def precision(self):
          
          if self._precision is None:
              cov = np.atleast_3d(self.covariance)
              self._precision = np.zeros(cov.shape)  # if one covariance per dimension
              for p in range(cov.shape[-1]):
                  self._precision[:, :, p] = pdinv(cov[:, :, p])[0]
          return self._precision
docs: Inverse of posterior covariance