Function working as a matlab script but not working when copied into a simulink block (Matlab Function)

I am trying to use the following code inside the Matlab Function Block of Simulink, its giving me size mismatch error while building the model. But when the same code is written as a matlab script and executed, it works perfectly. I suspect that the error arises because of how load function works for simulink. Can anyone provide some pointers on how to modify the code in order to avoid this mismatch in the behaviour of matlab and simulink?

data = coder.load("values.mat");

a = {data.w.l_0,data.w.l_1,data.w.l_2};

b = {data.g.l_0, data.g.l_1, data.g.l_2};

b = {data.s.l_0, data.s.l_1, data.s.l_2};

ctl = 0.0;
x = [0.3,0.03,0.03,0.03];
ctl = compute_output(x, a, b, c, 3);

[Sandeep Mishra]

Hi @ASHWIN ARAVIND

Can you please provide the specific error message and the MATLAB release version you're using?

Additionally, can you share the "values.mat" file, so that it would help community understand and reproduce the issue.

[ASHWIN]

Hi Sandeep, it is not possible to share the original .mat file. I will create a sharable version and attach it with the question. Thank you.

Answer 1

[Githin George]

Hi Aswin,

I feel that we are missing some elements here, like the inputs and outputs of the MATLAB Function Block, the variable definition for “c”, the “compute_output” function etc.

But with the limited information provided I am able to see that the provided code is supported in MATLAB Function block. So, the issue may lie with the MAT file contents or additional context that we are missing here (Note that I am using a dummy “compute_output” function and dummy MAT files).

I am attaching my model and related code here. Please provide additional details so that I can try from my end in case you are still facing issues.

Note that I am doing only Simulation and not Code Generation.

[ASHWIN]

Thank you for providing a detailed response. I will go through your implementation and try to see if that helps. Yes, I need the Code Generation feature, which may also be the source of the issue here.

[Githin George]

Sure, let me know if it works.