A Reference Input node () is similar to the Selectable Input node but the valid values are entities in a list in the model. The list can be the physics features, either the siblings to this feature of the siblings to the parent feature, the physics, the multiphysics coupling features, the materials, or the coordinate systems in the model. It is possible to add more valid values, typically None, by adding an Allowed Values feature as a subnode to the Reference Input node. You can also define a model entity list for the reference input by adding an Allowed References subnode. You can add multiple Allowed References subnodes to combine different model entity lists into one single reference list.

To add a Reference Input, first add a feature node or property node (for example, a Generic Feature, Domain Condition, or Device Model Feature), then:

The Settings window of a reference input has the following sections:

Almost the same as for the User Input.

From the Dimension list you can choose Scalar (the default), Vector (3x1), Changeable, or Custom to define the dimension of the reference input.

The Default value list can either be the First allowed value (the default) or Custom default. The latter allows you to enter an arbitrary default value as long as it is among the allowed values defined for the input.

See User Input for the rest of the settings.