problem with the exercise 6

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LAUJJL
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problem with the exercise 6

Post by LAUJJL »

Hi

i have followed three times the exercise 6 and generated the cows6 model joined. it has an error:something like missing a value for cows(id) or something like this. i tried to understand it.
I join the model. Another problem: the exercise6 complete is not complete! Otherwise I would have found the answer by myself.
i changed the extension from vmdl to mdl to allow the uploading. One has to change the extension once downloaded.

Regards.

JJ
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cows6.mdl
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dangoldner
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Re: problem with the exercise 6

Post by dangoldner »

Hello JJ,
Thank you for working the exercises so diligently! Three things:

1. Do you have the sample model called Exercise 6 Complete from the installation? In case it was not supplied, I have attached it. It is the correct result of the completion of exercise 6.

2. Note that the attachment is a zip file, because a Ventity .vmdl file is not enough to run a simulation. The entire folder structure is required. See The Ventity Workspace > Files and Folders in Help for more information.

3. Are the following warnings the same as you are seeing?

Code: Select all

08/03/2015 17:27:22: Warning in model Exercise 6 Complete : [0]01/01/0001 Unable to reference Entity Type [pasture] from cow [Cow-13] using Attribute [pasture]  = "thistle hill" 
08/03/2015 17:27:22: Warning in model Exercise 6 Complete : [0]01/01/0001 Undefined value for variable [available consumption rate] in Cow-13.
08/03/2015 17:27:22: Warning in model Exercise 6 Complete : [0]01/01/0001 Unable to reference Entity Type [pasture] from cow [Cow-14] using Attribute [pasture]  = "thistle hill" 
08/03/2015 17:27:22: Warning in model Exercise 6 Complete : [0]01/01/0001 Undefined value for variable [available consumption rate] in Cow-14.
If so, these are purposely a part of the training exercise. The idea is that even though two of the cow entities (#'s 13 and 14) have been assigned to a pasture called Thistle Hill, and no such pasture was included in the run, the model will still run. However, those two cows cannot get information from their assigned pasture entity, because it is not present in the run.

I ran your attached file (first I renamed it then placed it in the folder structure as described above), and got the errors above. If these are NOT the errors you are seeing, please post the error details. And please let us know if this doesn't address your question.
Attachments
Exercise 6 Complete.zip
Completed model from Exercise 6
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LAUJJL
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Re: problem with the exercise 6

Post by LAUJJL »

Hi
The exercise 6 complete works right. I saw the difference between the cows6 and the exercise 6 complete. There is a missing value ??? in the pasture references. See the model joined.
But I did not find the same reference in the pasture in the exercise 6 complete. So I do not know which value I must replace the ???. Is there such a reference in the exercise 6 complete and where is it?
Regards.
JJ
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cows6.zip
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dangoldner
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Re: problem with the exercise 6

Post by dangoldner »

Hello JJ,

The cows6 model you posted has an extra "cow" reference in the pasture entity definition (see screenshot, attached).

Every cow needs a "pasture" reference, which cows6 has correctly formed.
Every pasture needs a reference to its collection of cows, which cows6 also has correctly formed.
But every pasture does not need a reference to an individual cow. The reference highlighted in the attached image may have been created by accident during the modeling process. Deleting it will solve the issue.

On our list of things we'd like to add is, clearer indications of when references are undefined and unused, as in this case.

Dan
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2015-08-04_9-12-45.png
2015-08-04_9-12-45.png (18.33 KiB) Viewed 5476 times
LAUJJL
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Re: problem with the exercise 6

Post by LAUJJL »

Hi Dan

Thank you for the reply.

Regards.

JJ
dangoldner
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Re: problem with the exercise 6

Post by dangoldner »

Of course! As you get to know the software, please keep us posted on things you'd like to see.
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