Requirements diagram: Derive relationship direction and composition

What is the direction of the derive relationship in the requirements diagram? Is the arrow is drawn from the high level requirement to the derived requirement?

I am using composition to represent levels in the requirements diagram. In this fashion the 1 level down in the composition hierarchy provides more detail to the requirement.
For example:


User interface

  /\
  \/
   |
   V

Multimedia playback

/\ /
/ /
| |
V V


Play audio Play video


So to me this says “Providing a user interface is composed of being able to playback multimedia, which is composed of playing audio and video.” Is this the correct usage?

Also, when would you use containment?

Hi Captain,

Thanks for your post. Using composition in your case is correct, and derive relationship does not fit into your case. According to SysML Specification v1.1:
“A DeriveReqt relationship is a dependency between two requirements in which a client requirement can be derived from
the supplier requirement.”

Attached you can see a sample of derived requirement which I picked from SysML Specification v1.1. Hope this helps.

Best regards,
Lilian Wong
sample_from_SynML_Spec.png

Great thanks Lilian. Time for me to read the SysML spec…

Hi Captain,

You are welcome. Please let me know if there is any inquiry again.

Best regards,
Lilian Wong

I just tried creating a report (custom requirements report loop) and the requirements list out of order. For example, Requirement ID 1.1 appears before Requirement ID 1 in the list. 1 is composed of 1.1, 1.2, … so they should logically appear after it.

Hi Captain,

Thanks for replying. I’ve forwarded the issue to our engineers to follow-up, and will let you know if there is any feedback.
And we will support sorting elements by Name and ID in VP Suite 4.1 SP1 or 4.2.

Best regards,
Lilian Wong

Hi Captain,

I would like to let you know that we fixed order of requirements with report template used, please update to latest patch (20091021g or later). More details about update to latest patch from:

Best regards,
Lilian Wong

Thanks for the quick fix.

Hi Captain,

You are welcome. Please let me know if there is anything we can help again.

Best regards,
Lilian Wong

In the report, when I create a diagram loop, how can I specify the output order of each requirements diagram?

EDIT
Ok, I found it. There is the ability to move up/move down the diagram in the Diagram Navigator pane. That order dictates the report generation order.

In the report generation, is it possible to output the tabular view of the requirements?

Hi user,

Thanks for your inquiry. We are sorry that we do not support generate requirement diagram in tabular view, but we plan to support this in VP Suite 4.2 (VP-UML 7.2).

By the way, you can export the requirement diagram to Excel file, the exported Excel file will contains the details exist in tabular view. For VP-UML, export Excel feature is available in Standard Edition or above.

Best regards,
Lilian Wong

I have a follow up…
It seems that I can’t sort the tabular view by requirement ID (or by any column for that matter). Can you enable this feature?

Looks like you have enabled the output of the requirements grid in the report generation with the latest patch. Thanks for that!

Hi Captain,

Thanks for replying and our engineers are working to support sort requirements by ID in tabular view. I’ll let you know if there is any news on this issue.

Best regards,
Lilian Wong

Hi Captain,

Sorry for my late response. We support sorting ID of requirements in tabular view of requirement diagram in latest patch (build sp1_20091125f). Please follow the steps in following link for update to latest patch:

Feel free to ask if you need any help. :slight_smile:

Best regards,
Lilian Wong

Looks good so far Lilian. Thank you for the great support; It is much appreciated.

Hi Captain,

You are welcome.

Best regards,
Lilian Wong

Is it possible to turn off the sort by column? Seems after you sort you can never un-sort.

Hi user,

Which diagram or shape are you referring to? I cannot locate the function you are talking about in requirement diagram.

Best regards,
Jick

Create a requirements diagram, switch to “Tabular View” (right click and click “Switch to tabular view…”). Create a few requirements. Now you can reorder with the up and down arrows, I use this to put higher priorities up top.

You can also reorder from the column headers, so click on the ID header and they will be sorted by ID. Problem is, that once a column header is sorted it seems impossible to turn that sort off. Usually programs have a click 3 times to take off the sort (1st click ascending, 2nd descending, 3rd=OFF). So whenever you want to prioritize your requirements and you hit the column sort, you are up the creak because it seems your prioritization ordering is gone and you have to live by your column sort. Either I’m missing something or the devs forgot to write the feature into their requirements/use cases while engineering VP.