SysML, UAF, UML, and UPDM Profiles > SysML profile > Constraint blocks > Constraint parameters > Constraint parameter (SysML item)
Constraint parameter (SysML item)
A Constraint Parameter is a parameter of a Constraint Property that can be bound to other Constraint Properties and Block Properties of type Value on a Parametric Diagram.
Create a Constraint Parameter through a Modeler explorer pane or a Parametric Diagram:
• In a Modeler pane, right-click the Constraint Block, point to New, point to SysML, and then click Constraint Parameter.
• On a Parametric Diagram:
◦ Click the Constraint Parameter button, and then click the appropriate Constraint Property.
◦ Drag the Value Type that is to type the Constraint Parameter to the Constraint Property on the Parametric diagram.
A Constraint Parameter uses a Value Type as a type. When creating a Constraint Parameter, you can create it untyped, but at a future time you must specify a type for it: right-click the Constraint Parameter, point to Set, and then click Type, Type (Redefinition Only) or Type (Top Level Definition).
After creating a Constraint Parameter:
• You can specify a default value through the Data Type tab of the Constraint Parameter's Property Pages.
• You can specify its multiplicity: right-click the Constraint Parameter, point to Set, and then click Multiplicity.
• You can set up the Constraint Parameter as read only: right-click the Constraint Parameter, point to Set, and then click Read Only.
• You can set up the Constraint Parameter as shared (not composite): right-click the Constraint Parameter, point to Set, and then click Is Composite.
• You can change its type: right-click the Constraint Parameter, point to Set, and then click Type, Type (Redefinition Only) or Type (Top Level Definition).
When shown on a Parametric Diagram, a Constraint Parameter's notation is as follows:
On a Parametric Diagram, you can populate a Constraint Property with its Constraint Parameters: right-click the Constraint Property, point to Populate, point to Nodes, and then click Constraint Parameters.
On a Constraint Block owned Parametric Diagram, you can populate the diagram with the owning Constraint Block's Constraint Parameters: right-click the diagram background, point to Populate, point to Nodes, and then click Constraint Parameters.
On a Parametric Diagram you can connect Constraint Parameters to other Constraint Parameters and Block Properties of type Value.
All Constraint Parameters are shown in the Constraint Blocks pane - expand the ConstraintParameter folder.
A Constraint Parameter is a UML Role that is stereotyped by the «ConstraintParameter» stereotype from the SysML profile.
The following sections provide information about how a Constraint Parameter is used in the model. For more information about a SysML diagram or item - click it.
Owned by
Constraint Block
Owns
Allocate - the Allocate is owned jointly by the Constraint Parameter and the associated item. The access permissions you have to an Allocate are determined by the access permissions you have to the item that is allocated from - you require write access to both items to create or delete an Allocate.
Binding Connector - the Binding Connector is owned jointly by the Constraint Parameter and the associated item.
Problem
Rationale
Refine (UML Standard profile) - the Refine relationship is owned jointly by the Constraint Parameter and the associated item. The access permissions you have to a Refine relationship are determined by the access permissions you have to the refined item.
Satisfy - the Satisfy relationship is owned jointly by the Constraint Parameter and the associated Requirement. The access permissions you have to a Satisfy relationship are determined by the access permissions you have to the Constraint Parameter.
Trace (UML Standard profile) - the Trace relationship is owned jointly by the Constraint Parameter and the associated item. The access permissions you have to a Trace relationship are determined by the access permissions you have to the item that is traced from.
Verify - the Verify relationship is owned jointly by the Constraint Parameter and the associated Requirement. The access permissions you have to a Verify relationship are determined by the access permissions you have to the Constraint Parameter.
Shown on these diagrams
Block Definition Diagram
Parametric Diagram
SysML Properties
• allocatedFrom - lists source items that are linked through Allocate relationships (on Allocated tab when item is allocated).
• allocatedTo - lists target items that are linked through Allocate relationships (on Allocated tab when item is allocated).