GaussNewtonModel.gradient
=========================

.. py:method:: t3toolbox.fitting.GaussNewtonModel.gradient()

   .. code-block:: python

      def gradient(self) -> t3m.T3Tangent:  # g = Π 𝒥ᵀ r (+ g_R), a tangent at frame


   The gradient ``g = geometry.project(𝒥ᵀ r)`` (the Gauss-Newton ``Jᵀr``), a tangent at frame,
   plus the regularizer gradient ``g_R`` when set.

   On the manifold geometry this is the gauged Riemannian gradient; on the corewise geometry it is
   the raw core gradient ``𝒥ᵀr`` (a tangent at ``(U,G,G,G)``, no ``Π``).