.. _method-bayes_calibration-wasabi-emulator-pce:

"""
pce
"""


Polynomial Chaos Expansion surrogate model


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

   method-bayes_calibration-wasabi-emulator-pce-p_refinement
   method-bayes_calibration-wasabi-emulator-pce-max_refinement_iterations
   method-bayes_calibration-wasabi-emulator-pce-quadrature_order
   method-bayes_calibration-wasabi-emulator-pce-sparse_grid_level
   method-bayes_calibration-wasabi-emulator-pce-cubature_integrand
   method-bayes_calibration-wasabi-emulator-pce-expansion_order
   method-bayes_calibration-wasabi-emulator-pce-orthogonal_least_interpolation
   method-bayes_calibration-wasabi-emulator-pce-import_expansion_file
   method-bayes_calibration-wasabi-emulator-pce-askey
   method-bayes_calibration-wasabi-emulator-pce-wiener
   method-bayes_calibration-wasabi-emulator-pce-normalized
   method-bayes_calibration-wasabi-emulator-pce-export_expansion_file
   method-bayes_calibration-wasabi-emulator-pce-diagonal_covariance
   method-bayes_calibration-wasabi-emulator-pce-full_covariance


**Specification**

- *Alias:* None

- *Arguments:* None


**Child Keywords:**

+-------------------------+--------------------+------------------------------------+-----------------------------------------------+
| Required/Optional       | Description of     | Dakota Keyword                     | Dakota Keyword Description                    |
|                         | Group              |                                    |                                               |
+=========================+====================+====================================+===============================================+
| Optional                                     | `p_refinement`__                   | Automatic polynomial order refinement         |
+----------------------------------------------+------------------------------------+-----------------------------------------------+
| Optional                                     | `max_refinement_iterations`__      | Maximum number of expansion refinement        |
|                                              |                                    | iterations                                    |
+-------------------------+--------------------+------------------------------------+-----------------------------------------------+
| Required (Choose One)   | Required (Choose   | `quadrature_order`__               | Order for tensor-products of Gaussian         |
|                         | One)               |                                    | quadrature rules                              |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `sparse_grid_level`__              | Level to use in sparse grid integration or    |
|                         |                    |                                    | interpolation                                 |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `cubature_integrand`__             | Cubature using Stroud rules and their         |
|                         |                    |                                    | extensions                                    |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `expansion_order`__                | The (initial) order of a polynomial expansion |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `orthogonal_least_interpolation`__ | Build a polynomial chaos expansion from       |
|                         |                    |                                    | simulation samples using orthogonal least     |
|                         |                    |                                    | interpolation.                                |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `import_expansion_file`__          | Build a Polynomial Chaos Expansion (PCE) by   |
|                         |                    |                                    | importing expansion coefficients and a        |
|                         |                    |                                    | corresponding multi-index from a file         |
+-------------------------+--------------------+------------------------------------+-----------------------------------------------+
| Optional (Choose One)   | Basis Polynomial   | `askey`__                          | Select the standardized random variables (and |
|                         | Family             |                                    | associated basis polynomials) from the Askey  |
|                         |                    |                                    | family that best match the user-specified     |
|                         |                    |                                    | random variables.                             |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `wiener`__                         | Use standard normal random variables (along   |
|                         |                    |                                    | with Hermite orthogonal basis polynomials)    |
|                         |                    |                                    | when transforming to a standardized           |
|                         |                    |                                    | probability space.                            |
+-------------------------+--------------------+------------------------------------+-----------------------------------------------+
| Optional                                     | `normalized`__                     | The normalized specification requests output  |
|                                              |                                    | of PCE coefficients that correspond to        |
|                                              |                                    | normalized orthogonal basis polynomials       |
+----------------------------------------------+------------------------------------+-----------------------------------------------+
| Optional                                     | `export_expansion_file`__          | Export the coefficients and multi-index of a  |
|                                              |                                    | Polynomial Chaos Expansion (PCE) to a file    |
+-------------------------+--------------------+------------------------------------+-----------------------------------------------+
| Optional (Choose One)   | Covariance Type    | `diagonal_covariance`__            | Display only the diagonal terms of the        |
|                         |                    |                                    | covariance matrix                             |
|                         |                    +------------------------------------+-----------------------------------------------+
|                         |                    | `full_covariance`__                | Display the full covariance matrix            |
+-------------------------+--------------------+------------------------------------+-----------------------------------------------+

.. __: method-bayes_calibration-wasabi-emulator-pce-p_refinement.html
__ method-bayes_calibration-wasabi-emulator-pce-max_refinement_iterations.html
__ method-bayes_calibration-wasabi-emulator-pce-quadrature_order.html
__ method-bayes_calibration-wasabi-emulator-pce-sparse_grid_level.html
__ method-bayes_calibration-wasabi-emulator-pce-cubature_integrand.html
__ method-bayes_calibration-wasabi-emulator-pce-expansion_order.html
__ method-bayes_calibration-wasabi-emulator-pce-orthogonal_least_interpolation.html
__ method-bayes_calibration-wasabi-emulator-pce-import_expansion_file.html
__ method-bayes_calibration-wasabi-emulator-pce-askey.html
__ method-bayes_calibration-wasabi-emulator-pce-wiener.html
__ method-bayes_calibration-wasabi-emulator-pce-normalized.html
__ method-bayes_calibration-wasabi-emulator-pce-export_expansion_file.html
__ method-bayes_calibration-wasabi-emulator-pce-diagonal_covariance.html
__ method-bayes_calibration-wasabi-emulator-pce-full_covariance.html



**Description**


Selects a polynomial chaos expansion (PCE) surrogate model to use in
the Bayesian likelihood calculations. Most specification options are
carried over for using PCE as a surrogate within the Bayesian framework.