Compiled exe app doesn't work on a function used within another function

So I have an app developed by MATLAB app designer. I have put my main backend code in a function and call that function on button press.

Here is my problem: While running in app designer everything is fine, but when I compile it as a stand-alone exe file and install it, the code doesn't work properly. So I used messages in different parts of code to debug it and I find out that it stops as soon as it reaches first function used in the main function. Here is a demonstration of my main code, note that this is the main function called by app designer:

function maincode
    x = 1;
    y = 2;
    
    z = secondfunction(x,y);
end

and my secondfunction is saved in another .m file (which I include in additional files before packaging)

function [sum] = secondfunction(inputArg1,inputArg2)
    syms x
    eqn = inputArg1*x + inputArg2 == 0;
    sum = solve(eqn,x);
end

UPDATE: I debuged it further and now I am 100% sure that it has to do something with "syms" and "solve".

[Walter Roberson]

and my secondfunction is saved in another .m file

You appear to have accidentally named your second function maincode .

In theory, functions are to be invoked according to the file name, not according to the function line name, so in theory as long as your second function file name was secondfunction.m the code should have worked. But it would not entirely surprise me if MATLAB gets confused by this situation.

[Amirreza Farzaneh]

I am sorry for my mistake Walter. I updated my question, see if you got anything? thank you.

Answer 1

[halleyhit]

In your second function, you are using syms, which is from Symbolic Math Toolbox. As shown in doc:

MATLAB Compiler and Simulink Compiler-Support for MATLAB, Simulink, and Toolboxes - MATLAB (mathworks.com)

It is not supported in Compiler workflow.

[Amirreza Farzaneh]

Thank you for your comment, what can I do about it? What are my alternatives?

[Walter Roberson]

 eqn = inputArg1*x + inputArg2 == 0;

That has an easy solution for x:

x = -inputArg2./inputArg1

[Amirreza Farzaneh]

Yes I know that, but it was a placeholder. My actual equations are ode and pde. Any way to compile them using syms? Or alternatives?

[Steven Lord]

Either solve them symbolically then generate a MATLAB function to evaluate that solution without using Symbolic Math Toolbox and use the generated function in your application (as shown on this documentation page) or switch to solving them numerically using the functions included in this documentation category.