A requirement is a kind of constraint that specifies stakeholder-imposed constraints that a design solution must satisfy to be a valid solution. There are both requirement definition and requirement usage elements, where a requirement usage is a usage of a requirement definition in some context. The context for multiple requirements can be provided by a package, a part, or another requirement. 

  • The informal text of a requirement is given by documentation comments in the body of a requirement definition or usage. 
  • If a requirement definition or usage is declared with a short name, this is also considered its requirement ID.

Creating requirement usage and definition elements

Creating requirement usage and definition elements via the Textual Editor

To create requirement usage and definition elements via the Textual Editor

  1. In the Textual Editor, place the cursor where you want to create the element and declare the keyword:

    1.  requirement def for a requirement definition.

    2.  requirement for a requirement usage.
  2. Specify the element name.
  3. (Optional) Specify the requirement in the element body.
  4. Click the Synchronize button.

requirement def MassRequirement {
   subject vehicle : Vehicle;
   doc /* The actual mass shall be less than or equal to the required mass. */
   attribute massRequired : MassValue;
}

requirement <'1'> fullVehicleMassLimit : MassRequirement {
   subject vehicle : Vehicle;
   attribute :>> massRequired = 2000 [kilogram];
}

Creating requirement usage and definition elements via the Create Element command

To create requirement usage and definition elements via the Create Element command

  1. In the Containment tree, right-click an element, and in the shortcut menu, click Create Element.

  2. In the Create Element dialog, select one of the following:
    1. requirement def to create a requirement definition element.
    2. requirement to create a requirement usage element.
  3. Name the element.
  4. (Optional) Specify the requirement.

Creating requirement usage definition elements via the view palette

To create requirement usage and definition elements via the view palette

  1. In the view palette, under the Requirements/Constraints group, click one of the following:
    1. The requirement def button to create a requirement definition element.
    2. The requirement button to create a requirement usage element.

      If the needed button is not displayed, click the down-facing arrow next to either the requirement or the requirement def button and select the needed button in the dropdown menu.

  2. Click in the view pane where you want to create the requirement symbol.
  3. (Optional) Specify the requirement.

Auto-creating requirement definition elements via the Extract Definition command

To auto-create requirement definition elements via the Extract Definition command