I just finished the C1M1 course. I completed all the steps and all unit tests passed and it said I could submit at that stage before heading to the non-graded Exercise 5. At that point it graded me 30/40 so I reviewed my past exercises to see if I completed everything. I believe that I did and again all the tests passed.
I decided to move onto Exercise 5, to see if that was the issue. I noticed a separate problem when plotting the predicted to actual values. It looked like predicted values weren’t being un-normalized as they appeared to look like a horizontal line and not close to the actual values. I couldn’t edit the sell so I tried to create a new one. I realized I needed access to the hours mean and std deviation so I went back to earlier sells to attempt to pull that out with the results_dict instantiated during prepare_data. I couldn’t quite figure it out and submitted again and that time got a 40/40. So two separate questions:
Any ideas on why it would’ve given me 75% the first time around? I didn’t change any core logic in the graded cells.
How do we unnormalize the data in this particular notebook for Exercise 5 so that it correctly displays the predicted v actual values?
Depending on the backend resources available for grading computations, sometimes a correct solution to an exercise or multiple exercises can come back as 0 results. If you read the “Submission Note”, it mentions this scenario, and asks you to just simply re-submit the assignment and it should work the next time (granted that you have successfully passed all of the tests within the notebook).
This is likely what happened in your case as well, since you didn’t change any code and got full grade on your next submission.
The assignment clearly mentions not to fiddle with areas of code which are not exercise cells. DO NOT CHANGE ANY PIECE OF CODE which you are not suppose to touch in an assignment. The areas in which you can and are suppose to change, the exercise and “EDITABLE CELLS”, clearly state that you can edit those.
If something is not working in an assignment the way it should, please do not change any existing code nor add anything new (because the issue will not be because of that), instead focus more so on making sure your exercise solutions are correct. And if you are passing the tests and are confident that your solutions are correct, try re-submitting a few times. If the problem persists, please post in this community so that we can help you out.
Again, I want to emphasise this point because learners do this and end up with all sorts of trouble, please do not try to change any existing code or add anything new. All of the code in the notebook is tested countless times and should work if your solution code is correct. If something is not behaving the way it should, it will not be because of something needs to be manipulated in the existing code, but because there is something wrong with the solutions. If you are passing the tests, and still not getting the expected behaviour in the notebook, please let us know.
As for normalising/unnormalizing, please continue with rest of the modules and courses, you’ll get to learn all of that and more.
Thanks so much for the quick response @Mubsi - appreciate the help. Will keep you posted if any other issues. Otherwise, will keep my hands off the uneditable cells and not add anything new Thanks for the reminder.
Thanks for the reminder.