.. _method-mesh_adaptive_search-variable_neighborhood_search:

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variable_neighborhood_search
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Percentage of evaluations to do to escape local minima.


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



**Specification**

- *Alias:* None

- *Arguments:* REAL

- *Default:* 0.0


**Description**


The ``variable_neighborhood_search`` keyword is used to set the
percentage (in decimal form) of function evaluations used to escape
local minima.  The mesh adaptive direct search method will try to
perform a maximum of that percentage of the function evaluations
within this more extensive search.

*Default Behavior*

By default, ``variable_neighborhood_search`` is not used.

*Usage Tips*

Using ``variable_neighborhood_search`` results in an increased number
of function evaluations.  If the desired result is a local minimum,
the added cost is of little or no value, so the recommendation is not
to use it.  If the desired result is the best local minimum possible
within a computational budget, then there is value in setting this
parameter.  Note that the higher the value, the greater the
computational cost.  The value should be no greater than 1.0.



**Examples**


The following example shows the syntax used to set
``variable_neighborhood_search``.


.. code-block::

    method
      mesh_adaptive_search
        seed = 1234
        variable_neighborhood_search = 0.1




