Why am I getting an undefined function handle error when calling parfeval in MATLAB R2024b?

I am encountering a "MATLAB:UndefinedFunction" error with the message, "Undefined function handle" when running a MATLAB script in conjunction with a SimBiology program in MATLAB R2024b. The program performs a set of model fits to experimental data by submitting each model fit to a cluster using "parfeval". The cluster consists of the host computer (running a MATLAB SimBiology Model Analyzer interface and runs the program) and five additional compute nodes. This issue only occurs after the SimBiology program has been run at least once with the parallel pool generated by the cluster. How can I resolve this error?

Answer 1

[MathWorks Support Team]

To resolve this issue, ensure that all helper functions called within the code are separated into different .M files. Next, pass all these files to the workers by calling the "addAttachedFiles" method in the entry point MATLAB code. 

For example:

p = parpool('YourCluster');
addAttachedFiles(p, ["function1.m", "function2.m", "function3.m", "function4.m", "function5.m", "function6.m", "function7.m"]);