Blurb::
String-valued discrete design set variables
Description::
Discrete design variables whose values come from a specified set of
admissible strings.

See :ref:`variables:usage` for tips on specifying discrete set
variables. Each string element value must be quoted and may contain
alphanumeric, dash, underscore, and colon. White space, quote
characters, and backslash/metacharacters are not permitted.

Topics::
discrete_variables, design_variables
Examples::
Two string variables whose values will be selected from the set of
provided elements. The first variable, 'linear solver', takes on
values from a set of three possible elements and the second variable,
'mesh_file', from a set of two possible elements.


.. code-block::

    discrete_design_set
      string 2
        descriptors           'linear_solver'  'mesh_file'
        elements_per_variable 3                2
        elements              'cg' 'gmres' 'direct'
                              'mesh64.exo' 'mesh128.exo'


Theory::

Faq::

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