.. _ngw-node-surrogate:

.. _ngw-surrogates:

=========
surrogate
=========

The Dakota GUI supports replacing components of NGW workflows with Dakota-generated surrogates files.  To do this, drag a "surrogate" node onto the canvas (from the Dakota folder in the Palette).

.. image:: img/NGW_Surrogates_1.png
   :alt: The surrogate node

A new surrogate node will have no input or output ports until we associate it with a surrogate file.  Open the Settings Editor for the node and select a Dakota surrogate file (both .bin and .txt formats are supported).

.. image:: img/NGW_Surrogates_2.png
   :alt: The surrogateFile field must be populated before the surrogate node can be used!

After selecting the surrogate, the node will auto-create the necessary input and output ports to interface with the surrogate as part of a workflow.

.. image:: img/NGW_Surrogates_3.png
   :alt: The surrogate node with inputs and outputs

|

.. image:: img/NGW_Surrogates_4.png
   :alt: An example workflow using a surrogate node

To learn more about Dakota surrogates, consult :ref:`the primary documentation on surrogates in Dakota. <models:surrogate>`