Periodic Feature

) is a special boundary condition that couples, usually by pointwise constraints, dependent variables on a source side to a destination side to create a periodic boundary condition, for example. It has similarities with the Pair Feature.

The major difference between a periodic feature and an ordinary feature lies in subnodes that define selections. For periodic features, there are two extra options in the list of the section: and . With these options you can specify to use the source or destination boundaries in the condition of a periodic feature; see Specifying Selections for more information.

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To add a under the branch, node: On the toolbar, select it from the menu, or

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To add a under the or , Right-click the or nodes to add this from the submenu.

The window is similar to the Generic Feature window.


	For information about the settings in the Identifiers and GUI Options sections, see the Generic Feature node.

Selection Settings

Except for a few excluded settings, the sections are described for the Generic Feature node; see Selection Settings. For a periodic feature, you do not have to specify the geometric entity level because it is always boundary level. The same is true for the entity type setting because the only setting that makes sense is periodic conditions on exterior boundaries.

Preferences

The check box is enables if you have added to the list in the section. Select that check box to use the simple method for deduction of a periodic boundary without taking into account the rotation between source and destination.


	For the other settings see Preferences, for the Generic Feature node.