error of min() function in matlab function block in simulink (v 2018b)

Dear Matlab community,

I am trying to implement the minimum search within a matlab function block in a simulink model.

I need to find the minimum element and hence its coordinates of a matrix so I used the following code where the matrix "a" may contain 'nans'

>> [r,c]=find(a==min(a,[],'all'),1,'first')

however, I get the error " Invalid option. Option must be 'omitnan' or 'includenan' ". I substituted 'omitnan' to 'all' option but I eneded up with a "size mismatch" error.

So I am now using a for loop to search the minimum in the matrix, but this slows down my code.

I saw that this issue could arise with matlab releases that are older than 2018b, but I am using 2018b.

Do you know if there are other ways to solve this problem? Am I doing something wrong?

thank you in advance

Andrea

Answer 1

[Ameer Hamza]

According to documentation, the 'all' option is not supported for code-generation in R2018b (i.e., it will not work in Simulink). Also, using find() with min() might be inefficient. Try following

[~, idx] = min(a(:));
[r, c] = ind2sub(size(a), idx)

[Andrea Valletta]

Thank you so much, it worked fine

[Ameer Hamza]

I am glad to be of help!