compute_dxi
===========

.. py:function:: t3toolbox.backend.probing.compute_dxi(var_tucker_cores, ww)

   .. code-block:: python

      def compute_dxi(
              var_tucker_cores:       typ.Union[typ.Sequence[NDArray], NDArray], # len=d. elm_shape=(nOi,Ni)
              ww:                     typ.Union[typ.Sequence[NDArray], NDArray], # len=d. elm_shape=(...,Ni)
      ) -> typ.Union[typ.Sequence[NDArray], NDArray]: # dxis. len=d, elm_shape=(...,nOi)


   Compute var-upward edge variables dxi.
   Used for probing a tangent vector.

   Same as compute_xi(), except with var_tucker_cores in place of tucker_cores.

   See Section 6.2.2, particularly Algorithm 7, in:
       Alger, N., Christierson, B., Chen, P., & Ghattas, O. (2026).
       "Tucker Tensor Train Taylor Series."
       arXiv preprint arXiv:2603.21141.
       `https://arxiv.org/abs/2603.21141 <https://arxiv.org/abs/2603.21141>`_

   .. seealso:: :py:obj:`compute_xi`, :py:obj:`compute_sigma`, :py:obj:`compute_tau`, :py:obj:`compute_deta`, :py:obj:`assemble_tangent_z`, :py:obj:`tv_probe`