ut3_apply_derivatives
=====================

.. py:function:: t3toolbox.backend.ut3_sampling.ut3_apply_derivatives(ww, pp, data, order)

   .. code-block:: python

      def ut3_apply_derivatives(
              ww:    typ.Sequence[NDArray],  # apply vectors X,        len=d, ith elm_shape=W+(Ni,)
              pp:    typ.Sequence[NDArray],  # perturbation vectors P, len=d, ith elm_shape=W+(Ni,)
              data:  UT3Data,
              order: int,                    # highest derivative order
      ) -> NDArray:                          # shape=(order+1,)+W+stack_shape


   Symmetric all-modes apply derivatives of a uniform Tucker tensor train (shares
   ``sampling_derivatives.t3_apply_derivatives``; a scalar jet per stack element). ``ww``/``pp`` packed to ``N``.