ufv_tied_variations_residual
============================

.. py:function:: t3toolbox.backend.sharing.ufv_tied_variations_residual(variations_data, shared_data, rcond = None)

   .. code-block:: python

      def ufv_tied_variations_residual(
              variations_data,    # UT3Variations .data: (tkv_sc, ttv_sc, shape, (4 masks)); stack = K + C
              shared_data:    'SharedFrameData',  # the frame's UNIFORM companion (ufv_shared_frame_data)
              rcond:          typ.Optional[float] = None,  # relative clip on the group spectrum; None -> dtype eps
      ) -> NDArray:  # shape = K + C; relative deviation per stack element (0 == already tied)


   The uniform twin of :py:func:`fv_tied_variations_residual`, on the MASKED variation content.

   Same single global Frobenius ratio with the ``K + C`` stack kept -- masked first, because padding is
   don't-care garbage and two tangents tied on their real content are tied whatever their padding
   holds. The core axes summed over are the supercore's trailing ``(nDi, Ni)``; the leading ``d`` axis
   is summed as well, since the norm spans all ``d`` cores.