MATLAB: Passing Transforming function to step method of matlab.system.System

MATLABMATLAB Compilermatlab.system.systemobject-orientedoopprogrammingstep method

Goal: Apply the transform object T to the input data x, in a specefic manner as class A states.
Description: I have a class which does a specefic analyis called T, and another class which want to deploy an object from T on the data, x, in a specific order (class A). A is inherited from matlab.system.System because I can develop my code easier using "step Method" and blah blah. Step method just takes variables and fi objects but not function_handle or a external object (btw why? is it possible in general?). So I import the T object to the A.Func property and pass it to step method. In step method I call the A.Func.do to perform my desired T analysis. I couldn't find any other way 🙁 (I'm newbie). But i constantly get a weird error which I don't understand.
Analysis class T:
 classdef T < handle
    properties
        N
    end
    methods
        % CONSTRUCTOR:
        function obj = T(n)
            if nargin == 1
                obj.N = n;
            else
                obj.N = 16;
            end
        end
        function y = do(x)
            y = abs(fft(x,obj.N));
        end
    end
 end
Structering Class A:
   classdef A < matlab.system.System
  properties
          W           % numeric properties
          Func        % function handle or object
      end
      methods
          % constructor
          function obj = A(Func,w)
              if nargin == 2
                  obj.W = w;
                  obj.Func = Func;
              else % you can use default assining in the properties instead...
                  obj.W = 16;
                  obj.Func = @(x) sin(x);
              end
          end
      end 
      methods (Access=protected)
          function y = stepImpl(obj,x)
              y = obj.Func.do(x)*obj.W;
          end
          function numIn = getNumInputsImpl(~)
              numIn = 1;
          end
      end   
   end
and the main script is:
clear all
clc
x = linspace(0,10*pi,100);
a = T(100);
b = A(T,3);
step(b,x)
but I get this error:
Error using T/do
Too many input arguments.
Error in A/stepImpl (line 30)
            y = obj.Func.do(x)*obj.W;
Error in Main (line 9)
step(b,x)
Class T Code:
http://pastebin.com/KhbsDAQy
Class A Code:
http://pastebin.com/RTiKf6Pz

Best Answer

Hi, Marry Christmass,
The problem was solved by a technique called object composition. Just for documenting, in the case of static method "." operator should be used. and with the superclass "@" operator. (and bunch of concepts about superiority/inferiority) ... however using direct call (some sort of overloading) was enough to have a working class:
Class A:
classdef A < matlab.system.System
  
  properties
    W           % numeric properties
    Func        % function handle or object
  end
  methods
    function obj = A(Func,w)
      if nargin == 2
        obj.W = w;
        obj.Func = Func;
      else 
        obj.W = 16;
        obj.Func = @(x) sin(x);
      end
    end
   
  end % method

  
  methods (Access=protected)
    
    function y = stepImpl(obj,x)
      y = do(obj.Func,x)*obj.W;
    end
    
    function numIn = getNumInputsImpl(~)
      numIn = 1;
    end
  end
  
end
Class T:
classdef T < handle
  properties
    N
  end
  methods
    
    function obj = T(n)
      if nargin == 0
        obj.N = 16;
      end
      if nargin == 1
        obj.N = n;
      end
    end
    function y = do(obj,x)
      y = abs(fft(x,obj.N));
    end
  end
  
end % method
Main Script:
clear all
clear classes
clc
x = linspace(0,10*pi,100);
a = T(100);
b = A(T,3);
step(b,x)
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