T3Variations.unstack
====================

.. py:method:: t3toolbox.frame_variations_format.T3Variations.unstack()

   .. code-block:: python

      def unstack(self):


   Unstack into an array-like tree.

   .. rubric:: Examples

   >>> import numpy as np
   >>> import t3toolbox.frame_variations_format as bvf
   >>> import t3toolbox.corewise as cw
   >>> np.random.seed(0)
   >>> rnd = lambda x: np.random.randn(*x)
   >>> ss = (2, 3)                                   # stack: unstack splits these leading axes
   >>> NN, nnU, nnD, rrL, rrR = (10, 11, 12), (8, 7, 8), (6, 7, 8), (2, 3, 4, 3), (5, 4, 6, 1)
   >>> tucker_variations = tuple(rnd(ss+(n, N)) for n, N in zip(nnD, NN))
   >>> tt_variations = tuple(rnd(ss+(rL, n, rR)) for rL, n, rR in zip(rrL[:-1], nnU, rrR[1:]))
   >>> V = bvf.T3Variations(tucker_variations, tt_variations)
   >>> VV = V.unstack()
   >>> print(len(VV), len(VV[0]))                    # nested tree shaped like the stack (2, 3)
   2 3
   >>> ii, jj = 1, 2                                 # the [ii][jj] leaf is the cores sliced at [ii, jj]
   >>> sliced = bvf.T3Variations(
   ...     tuple(c[ii, jj] for c in tucker_variations), tuple(c[ii, jj] for c in tt_variations))
   >>> print(np.allclose(cw.corewise_norm(cw.corewise_sub(VV[ii][jj].data, sliced.data)), 0.0))
   True