Ardunino - Cannot access method 'getInterruptTerminals' in class arduino

Greetings, I've new to matlab and arduino, this is probably and easy question

I've been trying to use the 'getInterruptTerminals' method but matlab reports the message "Cannot access method in class arduino :(

This is the code...

a = arduino('COM3','Uno')
terminals = getInterruptTerminals(a)

This line is in the documentation

arduinoObj = obj.Parent; 

which should be...

a = arduino('COM3','Uno')

but I'm not sure about this line

arduinoObj = obj.Parent;

what does obj.Parent mean in this case, what is the parent?

Any help is appreciated.

Darnell

EDIT, I've been reading though the web site, its not as trivial as I thought, I may have to create a class to access this method, the is a bit new to me, I hope I'm on the right track.