Variability Modeling > Modeling variability in a model > Reference topics for variability modeling (diagrams, items and relationships) > Variability relationships > Variability dependency
  
Variability dependency
For automation interface information about a Variability Dependency (Dependency of type Variability through the automation interface), see Dependency (automation interface).
A Variability Dependency is a Dependency of type Variability. For reference information about Dependencies, see Dependency (dictionary item).
A Variability Dependency specifies that a Variant is an option for a Variation Point:
An optional Variability Dependency specifies that a Variant can be included for a Variation Point.
A mandatory Variability Dependency specifies that a Variant must be included when the Variation Point is included.
Create a Variability Dependency through any diagram:
Click the Optional Variability Dependency toolbar button, click the Variation Point or Alternative Choice, and then click the Variant.
Click the Mandatory Variability Dependency toolbar button, click the Variation Point, and then click the Variant.
When shown on a diagram, a Variability Dependency's notation is as follows:
For information about the View Options available for this symbol, see Variability view options - all diagrams.
On a diagram you can populate Variability Dependencies in the following ways:
Right-click the diagram background, point to Populate, and then click 'Variability, Artifact, Constraint Dependencies'.
This command populates missing Artifact, Excludes, Requires and Variability Dependencies between items shown on the diagram.
Right-click a Variation Point, Alternative Choice or Variant, point to Populate, and then click Variability Dependencies.
This command populates missing Variability Dependencies for the item you right-clicked, adding to the diagram any Variation Points, Alternative Choices or Variants that are required to show those missing Variation Dependencies.
Note that only one Variability Dependency can be created between two items. If you create a Variability Dependency between two items and a Variability Dependency relationship already exists between those two items (either directly or via an Alternative Choice):
If the existing Variability Dependency is not shown on the diagram, that Requires Dependency is added to the diagram.
If the existing Variability Dependency is shown on the diagram, Modeler prevents you from creating another Variability Dependency.
In the Modeler panes, a short-cut symbol on the Variability Dependency's icon indicates that the item is a stub. For more information, see Stubs.