How to make a kind of interaction between reference solution and learner template in Matlab Grader?

I want to make different solutions and data to different people according to their id no#. So i need to make a way that a student writes in his ID in the learner and by that the reference solution can read this number and generate values specific to that ID No#. and then i need the learner template to read these variables and display them to the student. Is that possible?

[Alfonso da Silva Saavedra]

Hi! I've done something like you need. Take a look to this example: https://github.com/alfonsovng/matlab-grader-utils/tree/main/examples/3-script-problem-personalized-values-image

Answer 1

[Cris LaPierre]

Simply put, no.

The order of execution is

1. Reference solution run to completion
2. Learner solution run to completion
3. Assessment tests run to completion

There is no ability to switch back and forth, running portions of them both.

Is this not something you could achieve using randomly generated numbers? Do the example problems 'Coordinate Transformations - Navigating a robot' or 'Finding a signal through the noise' provide potential solutions? The randomly generated numbers mean each student will have different data to work with, but because both the reference and learner workspaces share the same seed, they will generate the same random numbers, allowing for automated assessment.

[Rami Noureddine]

Great, i was thinking that different random numbers will be generated, that's why i thought if there is a way where i can read these numbers from the reference solution to learner template.

Thanks for your reply

[Toby Driscoll]

I understand and have used the fact that the same random numbers are found in the reference and learner spaces.

However, is there a way to ensure that each learner gets random values, but the same values on every execution instance? The use case I have in mind is for them to tune a parameter to reach a target final value in an initial-value problem. I want to use some randomization in the initial condtiions so that the students can't just share the answer, but then they need to be able to have repeated tries on the same data.

[Cris LaPierre]

It's best to start a new post for new questions. It keeps the discussion cleaner.

However, since you are here, l'll add that there is no built-in way to do this. MATLAB Grader uses a stateless server, meaning the connections are transactional. There is nothing on the backend that keeps a variable persisting for specific users. That means any conditions like this would need to be written into the problem itself.

[Andrew Pomfret]

It would be really helpful, in a future update, if some hash of the user ID were to be available in the workspace variables. That would allow MATLAB Grader to remain stateless, but it would allow us as problem authors to use the unique per-user values to create repeatable but user-unique problems.

[Justin Wyss-Gallifent]

I'm late to the post but I agree with Andrew here. This seems like an easy(ish) thing that would be immensely helpful.

[Jeff Alderson]

By design, MATLAB Grader solutions do not have access to personally identifiable information about students.

If you were to provide a P-coded function that accepts an input in the form of a Student ID that the learner provides in their solution, you could use that ID as an index to look up data from another P-coded file and return any variable you wish. You could reuse such a function in multiple problems, and include a note in your problem description that the student must provide their own Student ID as an input to your custom function at the start of their solution.

There may be another MATLAB Answers article that demonstrates this, and I will link back to it when I can find it.