Signal Processing onramp - Signal measurements. Answer incorrect even though the code is correct according to the solution.

Why does it show an error when I have selected 't' for X-axis data. Please help.

[Apurva Bhardwaj]

i am also facing the exact same issue @MathWorks Support Team please look into this we wont get aicte certificate otherwise

[DGM]

Seems multiple people are having this same problem today.

https://www.mathworks.com/matlabcentral/answers/2021321-issue-with-signal-processing-onramp-course-code-submission

https://www.mathworks.com/matlabcentral/answers/2021236-i-have-faced-an-issue-while-completing-signal-processing-onramp-course-on-matlab

https://www.mathworks.com/matlabcentral/answers/2021176-signal-processing-onramp-signal-measurements-answer-incorrect-even-though-the-code-is-correct-acc

https://www.mathworks.com/matlabcentral/answers/2021446-test-results-incorrect-1-does-maxindices-exist-2-is-findquakes-defined-correctly-3-is-t

[Purushotham]

i faced the same problem. I have been working on it for so long and still havent found any solution to it.I hope someone will respond to us.

[Kinshuk Gaurav]

same isuue

[Akash]

Same issue makes me frustrated!

[Matteo Mascanzoni]

Same

[Kesava]

same also happen for me please explain this..

Answer 1

[Renee Coetsee]

Thank you for reporting this issue. This is a known bug and we are actively working on fixing it in the course.

In the meantime, the workaround for Task 4 to

1. Click See Solution (left of the Submit button)
2. Copy the entire solution from the solution script into the working script
3. Submit Task 4

If that doesn't work, copy and paste the following code for Task 4:

% Find local maxima
maxIndices = islocalmax(pwr,"SamplePoints",t);
% Display results
figure
plot(t,pwr,"Color",[77 190 238]/255,"DisplayName","Input data")
hold on
% Plot local maxima
plot(t(maxIndices),pwr(maxIndices),"^","Color",[217 83 25]/255,...
    "MarkerFaceColor",[217 83 25]/255,"DisplayName","Local maxima")
title("Number of extrema: " + nnz(maxIndices))
hold off
legend
xlabel("t")

Then in Task 5, Reset the script (left of the Submit button) and complete Task 5 normally.

[Kruthi.R]

Thank You for helping us out @Renee Coetsee.

The code in the solution did not work and it still showed an error. I tried writing my own code but there was some error in that as well.

[Venkat Ramana]

Thankyou.. This code worked for me. But for task5 the reset option is not working.

I has to again submit the task by changing the line in code.

maxIndices = islocalmax(pwr,"maxProminence",10,"SamplePoints",t);

[Renee Coetsee]

@Kruthi.R are you still having an issue? If so, please post a screenshot of the code you are submitting for Task 4. Thank you!

[Renee Coetsee]

This issue should now be fixed and you should not need to use the workaround to complete the task. Please comment if you are still having issues with this task!