compute_deta_tilde_jets
=======================

.. py:function:: t3toolbox.backend.sampling_derivatives.compute_deta_tilde_jets(up_tucker_cores, ztildes)

   .. code-block:: python

      def compute_deta_tilde_jets(
              up_tucker_cores:    typ.Sequence[NDArray],  # U.  len=d, elm_shape=C+(nUi,Ni)
              ztildes:            typ.Sequence[NDArray],  # residual jets, len=d, elm_shape=(order+1,)+W+K+C+(Ni,)
      ) -> typ.Tuple[NDArray, ...]:                       # deta_tildes. len=d, elm_shape=(order+1,)+W+K+C+(nUi,)


   Adjoint-up edge-variable jets: ``deta_tilde_i = U_i r_i`` (contract the ambient mode, order
   diagonal). The 1-internal-edge (Tucker) case -- the order axis just rides through (no trs). The
   residual carries the tangent stack K (the forward output's K), which rides through.