MATLAB Documentation for OOP
(For reference by students)

NARGIN
Definition	Number of function input arguments. Inside the body of a user-defined function, NARGIN returns the number of input arguments that were used to call the function.
Example	function acct = BankAccount(data) if nargin == 0                            acct.balance = 0;    acct = class(acct,'BankAccount'); elseif isa(data, 'BankAccount')              acct = data; else    acct.balance = data;    acct = class(acct,'BankAccount'); end   In this example, if the number of input arguments was 0, then it creates a new field called balance in the class BankAccount