How to 'monitor' m file based dynamic function from GUI?

Hi all

I have a bunch functions representing dynamic of power system (generator, control, transmission lines, etc) in matlab m file. I call them from main function in m file as well. what i want to do is that when I'm simulating this dynamic model from t_start to t_end, I want to capture some variable changes (during this period)in my model then display it in GUI. so it resembles monitoring system. I tried to call the main function from GUI, but I can't get what i want i.e monitoring variables change.

Can Anyone give a suggestion?

best regard

Ali

p.s due to its big size, I can't post the m file here