CLAD Sample Exam 1, question 2:

[chrisking]

CLAD Sample Exam 1, question 2: can a wire be used to pass date between 2 llps that are intended to be runn in parallel?  CLAD Sample exam1  provides the following url as an answer:  http://zone.ni.com/devzone/cda/tut/p/id/9393 . This doesn’t explain the answer. Please provide a correct explanation.

[MikeS81]

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@chrisking wrote:

CLAD Sample Exam 1, question 2: can a wire be used to pass date between 2 llps that are intended to be runn in parallel?  CLAD Sample exam1  provides the following url as an answer:  http://zone.ni.com/devzone/cda/tut/p/id/9393 . This doesn’t explain the answer. Please provide a correct explanation.

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Hi chrisking,

the answer is no. If they are connected by a wire to pass data from one loop to the other, then they are (because of the data flow) not running in parallel.

Mike

[RavensFan]

That page is about parallel for loops, not about loops run in parallel.

The answer is no, because when you use a wire between two loops, data flow says the wire won't execute until the loop sourcing that wire completes.  Thus the 2nd loop becomes dependent on the completion of the 1st loop, thus they are not in parallel.

[NIquist]

Is that the actual wording?  Why can't they make these questions less ambiguous?   Just because you intend for the loops to run in parallel doesn't mean they actually do it.  BUT, the data will still be passed between the loops eventually, so technically, YES, a wire can be used.  Why didn't the question just say: "two loops that ARE running in parallel"?

[KathrynB]

I think I agree with that being a poor explanation for a link from the exam. However, that is a (relatively) new set of information, and I'm wondering if it has overwritten the information that would have been made more sense. It looks like the link tells us about useful things in LV2009+ but, given that the exam is meant to be a little more generic as I understood it, this is now an odd connection.

Basic explanation about the situation however:

A wire can't be used to pass data between a loops running in parallel for a simple oand obvious reason. LabVIEW programs are controlled by data flow. Whichever loop has the wire as an input would have to wait for the other loop to complete (as the wire has to be an output from that loop) before it could run, thereby removing the availability of parallelism.

[tbob]

Very ambiguous question indeed since there is no such thing as a wire between two parallel loops.  It is an impossibility because the addition of a wire between two loops precludes the possibility that they can run in parallel.  I really wish NI would reconsider the way they word their questions.  Ambiguity is rampant throughout all their exams.

[B_Spears]

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@NIquist wrote:

Is that the actual wording?  Why can't they make these questions less ambiguous?   Just because you intend for the loops to run in parallel doesn't mean they actually do it.  BUT, the data will still be passed between the loops eventually, so technically, YES, a wire can be used.  Why didn't the question just say: "two loops that ARE running in parallel"?

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The wording actually seems to be pretty decent. Two loops cannot be running in parallel if there is a wire running between them. The situation you describe--where one loop stops, data is passed, then the other loop begins--does NOT describe two loops running in parallel, rather two loops running sequentially.

When the question says "intends", it asks you to play the part of the designer of the code: if you want to have data passed between two loops, how would you design that? The answer is certainly not a wire.

[NIquist]

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@B Spears wrote:

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@NIquist wrote:

Is that the actual wording?  Why can't they make these questions less ambiguous?   Just because you intend for the loops to run in parallel doesn't mean they actually do it.  BUT, the data will still be passed between the loops eventually, so technically, YES, a wire can be used.  Why didn't the question just say: "two loops that ARE running in parallel"?

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The wording actually seems to be pretty decent. Two loops cannot be running in parallel if there is a wire running between them. The situation you describe--where one loop stops, data is passed, then the other loop begins--does NOT describe two loops running in parallel, rather two loops running sequentially.

When the question says "intends", it asks you to play the part of the designer of the code: if you want to have data passed between two loops, how would you design that? The answer is certainly not a wire.

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True, but the fact that we're even discussing the semantics proves that it's confusing.  I'm sure NI has a tough time coming up with multiple CLAD versions covering essentially the same questions but those questions should be testing for knowledge of LabVIEW, not English Language.  A test taker should be able to focus on the what a question is asking and not how it's being asked.

[B_Spears]

Re: NIquist

I wholeheartedly agree! Confusing wording seems to be a consistent complaint, especially among the old CLD-R, though I heard that has been addressed with the most recent update. For the most part I think they do a great job, but I believe the NI Certification dept should more carefully consider that they are writing these exams for a worldwide audience, many of whom do not speak English as their first language. I do know they vet them out internally, but these frequent discussions on this topic here in the forums proves that more emphasis still needs to be placed on that.

[tbob]

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@B Spears wrote:

Re: NIquist

I wholeheartedly agree! Confusing wording seems to be a consistent complaint, especially among the old CLD-R, though I heard that has been addressed with the most recent update. For the most part I think they do a great job, but I believe the NI Certification dept should more carefully consider that they are writing these exams for a worldwide audience, many of whom do not speak English as their first language. I do know they vet them out internally, but these frequent discussions on this topic here in the forums proves that more emphasis still needs to be placed on that.

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Although I agree about ambiguous wording, I must say that the group at NI that makes the questions consists of a wide variety of people, including some who's first language is not English.  It is an extremely difficult task to create fairly worded questions.  They are doing a good job, but there is still plenty of room for improvement.  Letting the test taker see which questions they missed will be a huge step in the right direction.  I believe this feature will be coming very soon.