Why do I get an "Unrecognized function" error when I run my MATLAB Compiler deployed standalone application?

I wrote MATLAB code or created an app in AppDesigner that runs without issues in MATLAB Desktop.

When I compile the app with MATLAB Compiler and deploy it, I get errors such as the following when I run the standalone application:

Unrecognized function or variable 'myFuncName'.
Undefined function or variable 'myFuncName'.
Reference to unknown function 'function_name' from FEVAL in stand-alone mode. 

Why do I get these errors when running the compiled version of my application but not when I run it from MATLAB Desktop?

Answer 1

[MathWorks Support Team]

When you encounter an "unrecognized function", "undefined function", or "unknown function" error in a compiled MATLAB application, it typically indicates missing dependencies during the compilation process.

Common causes include:

• Function not on path: Ensure all functions are on the MATLAB path during compilation. Test your app or function before you compile it.
• P-File Dependencies: Without the M-file source code, dependency analysis cannot detect dependencies for P-files. The tool mentioned in this MATLAB answer can help.
• String arguments: Functions used in strings passed to 'feval', 'eval', 'evalc', or as ODE solver arguments cannot be located by dependency analysis.
• Callback Strings: MATLAB Compiler does not look for functions in callback strings. Change the string reference to your function to a function handle.

To include any function dependencies explicitly, you can add %#function pragma statements to your code:

Pragma to help MATLAB Compiler locate functions - MATLAB %#function (mathworks.com)

Refer to the "Callback Problems Due to Missing Functions" section on the following page for further details, examples, and workarounds for missing dependencies:

MATLAB Compiler Limitations - MATLAB & Simulink (mathworks.com)