MATLAB: Bizarre value class behavior

classes value problemMATLABoop

Below is a self-explanatory VALUE class I developed for purposes of illustration.
      classdef ClassA
          properties
              x;
              y;
          end
          methods
             function obj = ClassA()
                obj.x = 0; 
                obj.y = 0;
             end
             function setX(obj, val)
                obj.x = val; 
             end       
             function setY(obj, val)
                obj.y = val; 
             end       
             function obj = set.x(obj, val)
                *obj* .x = val; 
             end
             function obj = set.y(obj, val)
                obj.y = val; 
             end
          end
      end
I instantiated it as follows:
a = ClassA();
Good. That worked. Now to test the setter methods:
a.x = 1;
a.y = 2;
Those worked too. But doing this:
a.setX(3)
a.setY(5)
causes the prompt to not echo the value of the properties as is done when the setter methods are used. Why? And when I enter the variable name in the prompt, the property values are echoed back but they do not change upon using setX and setY. This is puzzling. I followed proper VALUE class syntax for setX and setY. Help please!

Best Answer

"I followed proper VALUE class syntax for setX and setY." &nbsp No, that's handle class syntax. With a value class you create a new instance, which you need to return.
With the class definition modified
    >> a = ClassA
    a = 
      ClassA with properties:
        x: 0
        y: 0
    >> a = a.setX( 17)
    a = 
      ClassA with properties:
        x: 17
        y: 0
or
    >> a = setY( a,117)
    a = 
      ClassA with properties:
        x: 17
        y: 117
where
    classdef ClassA
        properties
            x;
            y;
        end
        methods
            function obj = ClassA()
                obj.x = 0;
                obj.y = 0;
            end
            function obj = setX(obj, val)
                obj.x = val;
            end
            function obj = setY(obj, val)
                obj.y = val;
            end
            function obj = set.x(obj, val)
                obj.x = val;
            end
            function obj = set.y(obj, val)
                obj.y = val;
            end
        end
    end
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