.. _method-optpp_pds:

"""""""""
optpp_pds
"""""""""


Simplex-based derivative free optimization method



**Topics**


package_optpp


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

   method-optpp_pds-search_scheme_size
   method-optpp_pds-max_iterations
   method-optpp_pds-convergence_tolerance
   method-optpp_pds-max_function_evaluations
   method-optpp_pds-scaling
   method-optpp_pds-model_pointer


**Specification**

- *Alias:* None

- *Arguments:* None


**Child Keywords:**

+-------------------------+--------------------+------------------------------+---------------------------------------------+
| Required/Optional       | Description of     | Dakota Keyword               | Dakota Keyword Description                  |
|                         | Group              |                              |                                             |
+=========================+====================+==============================+=============================================+
| Optional                                     | `search_scheme_size`__       | Number of points to be used in the direct   |
|                                              |                              | search template                             |
+----------------------------------------------+------------------------------+---------------------------------------------+
| Optional                                     | `max_iterations`__           | Number of iterations allowed for optimizers |
|                                              |                              | and adaptive UQ methods                     |
+----------------------------------------------+------------------------------+---------------------------------------------+
| Optional                                     | `convergence_tolerance`__    | Stopping criterion based on objective       |
|                                              |                              | function or statistics convergence          |
+----------------------------------------------+------------------------------+---------------------------------------------+
| Optional                                     | `max_function_evaluations`__ | Number of function evaluations allowed for  |
|                                              |                              | optimizers                                  |
+----------------------------------------------+------------------------------+---------------------------------------------+
| Optional                                     | `scaling`__                  | Turn on scaling for variables, responses,   |
|                                              |                              | and constraints                             |
+----------------------------------------------+------------------------------+---------------------------------------------+
| Optional                                     | `model_pointer`__            | Identifier for model block to be used by a  |
|                                              |                              | method                                      |
+----------------------------------------------+------------------------------+---------------------------------------------+

.. __: method-optpp_pds-search_scheme_size.html
__ method-optpp_pds-max_iterations.html
__ method-optpp_pds-convergence_tolerance.html
__ method-optpp_pds-max_function_evaluations.html
__ method-optpp_pds-scaling.html
__ method-optpp_pds-model_pointer.html



**Description**


The direct search algorithm, PDS (parallel direct search method),
supports bound constraints.

The PDS method can directly exploit asynchronous evaluations; however,
this capability has not yet been implemented in Dakota.

See :ref:`topic-package_optpp` for info related to all ``optpp`` methods.