T3Tangent.stack_tangents
========================

.. py:method:: t3toolbox.manifold.T3Tangent.stack_tangents(tree)
   :staticmethod:


   .. code-block:: python

      def stack_tangents(tree) -> 'T3Tangent':


   Stack a ``K``-shaped tree of tangents (sharing one frame) into a tangent-stacked T3Tangent.

   Inverse of :py:meth:`unstack_tangents`. Requires every leaf to be at the **same frame** (the
   same-frame numerical check, as in :py:meth:`corewise_inner` / :py:meth:`__add__`): the tangents
   being stacked must live in the same tangent space. The first leaf's frame is reused and the
   variations are stacked over the new outer tangent stack ``K``.