Dear @Abraham
In order for us to run your code, you also need to provide all the data and models, e.g. myPCE_LARSa.
However, I think the problem is that you specify ModelOpts.Parameters = myRFInput and therefore the function handle assigned to ModelOpts.mHandle must take this additional argument, as described in the manual. I recommend you to take another close look at the manual (section 2.1.1):
And are you sure you really want the ModelOpts.Parameters? From the code you showed me, it looks like myPCE_LARSa wouldn’t do anything with this additional argument.
Best regards
Styfen