Using uni-directional references

Question

Hi Jan,

I'm working on a "reverse" reference in an FMEA table from failure cause to Failure, and ultimately requirements trace linked to it. The following is a derived property from "Failure Cause (derived FMEA/DC only)" profile. I named it "Failure linked to cause in this row."

--Navigate from Cause to Failure
self.mediniGetOpposites('failureCauses')

This gives me the FMEA failure entry [MF001], shown here:

Now, what I'd like to do is access the proxy element it represents (the Malfunction from the Safety Model). I tried using a type cast as shown here:

--trying to access proxy element, malfunction
-- this code does not work
self.mediniGetOpposites('failureCauses').oclAsType(safetyModel::Malfunction)

That displayed nothing. I tried this several different ways, like adding the .element term various places. I seem to be stuck here. This is where I need help

As I mentioned above this is an intermediate step to what I ultimately want, which is to show the requirements trace linked to the Failure in this row of the FMEA. I know this can be done by creating a Failure profile property in this manner:

--failure profile, finds linked requirements
--works
self.element.oclAsType(safetyModel::Malfunction).mediniGetTracedElements(safetygoals::SafetyRequirement)

But I want to take that information (requirements linked to Failure) and find the intersection of it with requirements linked to my cause. So the final outcome would be a custom column, for each cause that shows only requirements trace linked to both the failure (in this particular row) and the cause.

So to look at that visually, in the following picture, my custom column would only display requirements B and C, but not A and D.

Your input would greatly be appreciated.

Thanks,

Jim Faucett

medini_1024169437 · Answer

Very cool!

The reason might be that intersection() is indeed not defined for Sequence:

Happy Scripting

Jan

medini_1045556505 · Answer

Looks like I may have found the solution. I converted each collection to a 'Set' using the '->asSet()' command. Works perfectly. Thanks again, Jan.

medini_1045556505 · Answer

Thank you, Jan.

Your solutions above both worked great. Using the first one seems like a cleaner method. So moving forward, I successfully added linked requirements for the cause and the failure in the following fashion:

--cause requirements
self.element.oclAsType(safetyModel::Malfunction).mediniGetTracedElements(safetygoals::SafetyRequirement)

--Failure Requirements
self.failureMode.element.oclAsType(safetyModel::Malfunction).mediniGetTracedElements(safetygoals::SafetyRequirement)

This gives me the following results:

So far, so good. Now the final step is I would like to return a result of elements that are contained in both sets. The 'intersection' seems like the right choice. So I tried to link the two code snippets above with intersection:

-- intersection of the 2 sets
-- this code does not work
self.failureMode.element.oclAsType(safetyModel::Malfunction).mediniGetTracedElements(safetygoals::SafetyRequirement)->intersection(self.element.oclAsType(safetyModel::Malfunction).mediniGetTracedElements(safetygoals::SafetyRequirement))

This returns a failed result, "Cannot find operation (intersection(Sequence(T))) for the type (Sequence(T)):

Oddly enough, if I replace the 'intersection' term with 'union,' I get this result:

I would expect using 'union' would filter out repeated results.

Can you help me figure out how to correct the 'intersection' result so I only get a result of "Requirement B" and "Requirement C"?

Thanks,

Jim Faucett