tv_entries_transpose
====================

.. py:function:: t3toolbox.backend.entries.tv_entries_transpose(c, index, frame, sum_over_probes = False)

   .. code-block:: python

      def tv_entries_transpose(
              c:          NDArray,                # residual, shape = W + C
              index:      NDArray,                # int, shape=(d,)+W (the indices whose entries c weights)
              frame:       typ.Tuple[typ.Sequence[NDArray], typ.Sequence[NDArray],
                                    typ.Sequence[NDArray], typ.Sequence[NDArray]],   # (up, down, left, right)
              sum_over_probes: bool = False,
      ) -> typ.Tuple[typ.Sequence[NDArray], typ.Sequence[NDArray]]:  # (dU_tildes, dG_tildes)


   Apply the transpose of :py:func:`tv_entries` -- scatter a residual ``c`` at ``index`` into a tangent.

   Identical to :py:func:`tv_apply_transpose` with the up-index ``xi-hat`` from fiber slicing and
   the apply vectors replaced by the unit vectors ``e_{index_k}`` (so the ``dU-tilde`` outer product
   *is* the entry scatter).

   .. seealso:: :py:obj:`tv_entries`, :py:obj:`tv_apply_transpose`