T3Frame.orthogonality_residual
==============================

.. py:method:: t3toolbox.frame_variations_format.T3Frame.orthogonality_residual()

   .. code-block:: python

      def orthogonality_residual(self) -> NDArray:  # shape = stack_shape (scalar/0-d when unstacked)


   Max absolute deviation of the orthogonal cores from identity, **per stack element** (shape
   ``stack_shape``; atol-independent; **cached**).

   The expensive part of :py:meth:`is_orthogonal` -- a fixed frame reused across an inner loop (e.g.
   the safe-mode ORTH precondition of :py:meth:`~t3toolbox.manifold.ManifoldGeometry.project` on the
   same frame every matvec) is contracted **once**, not per call.