To define an HDMR model, follow the procedure below:
* click the '''Add''' button in the "HDMR ModelsModel Definition" section of the dialog to open up the '''Add HDMR Model Dialog'''. At the bottom of this dialog, you can see a list of all the available [[EM.Cube]] standard output [[parameters]]. This list may vary depending on the types of sources and observables you have defined in your project.
* Choose a name for your HDMR model. Make sure that this name is unique and does not conflict with the existing data file names in your project's folder.
* Type in any mathematical expressions in the boxes labeled '''Expression'''. If you select the name of any standard parameter in the table and double-click on it, it will be reflected in the expression box.
* You can have different names for your HDMR model and its model file with an '''.HDM''' file extension. But it is recommended that you choose the same name. Select one of the available options in the dropdown list labeled '''Logical Operator'''. The default operator is '''"== (Equal To)"'''.* Once the construction definition of your objective HDMR model is complete, click the '''OK''' button on the dialog to close it and return to the Objectives HDMR Settings dialog.
You will see your new objective HDMR added to the Objective HDMR Model List table. You can modify a design objective model definition using the {{key|Edit}} button of the Objectives this dialog. Only design objectives that contain the logical operator "==" You can also define more than one HDMR model at a time. Such models will be used as an [[optimization]] goal. All generated using the design objectives that contain a logical operator other than "==" are treated as [[optimization]] constraintssame simulation runs. This means that the optimizer algorithm first tries However, it is recommended not to minimize an error function that is based on the goals solely and then it verifies that the constraints are satisfied additionallygenerate unrelated models together.
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<td> [[Image:Variable31.png|thumb|300px280px|Defining an objective involving S parameters.]] </td><td> [[Image:Variable34.png|thumb|300px480px|Defining an objective involving antenna directivity.]] </td>
</tr>
</table>