.. _model-adapted_basis-truth_model_pointer-dimension:

"""""""""
dimension
"""""""""


Prescribe the number of active dimensions


.. toctree::
   :hidden:
   :maxdepth: 1



**Specification**

- *Alias:* None

- *Arguments:* INTEGER


**Description**


If a prescribed dimension for the rotation matrix is desired, this can be specified with the keywork ``dimension``. In this case, the algorithm does not use the ``truncation_method`` or the ``truncation_tolerance`` to determine the truncation of the rotation matrix, but it just selects the first :math:`d`  dimensions, where :math:`d`  is assigned by ``dimension``.



**Examples**


The following block


.. code-block::

    model
      id_model = 'SUBSPACE'
      adapted_basis
        truth_model_pointer = 'FULLSPACE'
        sparse_grid_level = 1
        dimension = 3


prescribes the selection of the first three most important directions to build the rotation matrix and the reduced model representation.