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This example shows how to generate code for a MATLAB^® value class and then view the generated code in the code generation report.

1. In a writable folder, create a MATLAB value class, Shape. Save the code as Shape.m.

   classdef Shape 
   % SHAPE Create a shape at coordinates 
   % centerX and centerY
       properties
           centerX;
           centerY;
       end
       properties (Dependent = true)
           area;
       end
       methods 
           function out = get.area(obj)
               out =  obj.getarea();
           end
           function obj = Shape(centerX,centerY)
               obj.centerX = centerX;
               obj.centerY = centerY;
           end
       end
       methods(Abstract = true)
           getarea(obj);
       end
       methods(Static)
           function d = distanceBetweenShapes(shape1,shape2)
               xDist = abs(shape1.centerX - shape2.centerX);
               yDist = abs(shape1.centerY - shape2.centerY);
               d = sqrt(xDist^2 + yDist^2);
           end
       end
   end  

2. In the same folder, create a class, Square, that is a subclass of Shape. Save the code as Square.m.

   classdef Square < Shape 
   % Create a Square at coordinates center X and center Y 
   % with sides of length of side
       properties
           side;
       end
       methods
           function obj = Square(side,centerX,centerY)
               obj@Shape(centerX,centerY);
               obj.side = side;
           end
           function Area = getarea(obj)
               Area = obj.side^2;
           end
       end
   end

3. In the same folder, create a class, Rhombus, that is a subclass of Shape. Save the code as Rhombus.m.

   classdef Rhombus < Shape
       properties
           diag1;
           diag2;
       end
       methods
           function obj = Rhombus(diag1,diag2,centerX,centerY)
               obj@Shape(centerX,centerY);
               obj.diag1 = diag1;
               obj.diag2 = diag2;
           end
           function Area = getarea(obj)
               Area = 0.5*obj.diag1*obj.diag2;
           end
       end
   end

4. Write a function that uses this class.

   function [TotalArea, Distance] =   use_shape
   %#codegen
   s = Square(2,1,2);
   r = Rhombus(3,4,7,10);
   TotalArea  = s.area + r.area;
   Distance = Shape.distanceBetweenShapes(s,r);  

5. Generate a static library for use_shape and generate a code generation report.

   codegen -config:lib -report use_shape

   codegen generates a C static library with the default name, use_shape, and supporting files in the default folder, codegen/lib/use_shape.

6. Click the View report link.

7. In the report, on the MATLAB code tab, click the link to the Rhombus class.

   The report displays the class definition of the Rhombus class and highlights the class constructor. On the Variables tab, it provides details of the variables used in the class. If a variable is a MATLAB object, by default, the report displays the object without displaying its properties. To view the list of properties, expand the list. Within the list of properties, the list of inherited properties is collapsed. In the following report, the lists of properties and inherited properties are expanded.

   

8. At the top right side of the report, expand the Calls list.

   The Calls list shows that there is a call to the Rhombus constructor from use_shape and that this constructor calls the Shape constructor.

   

9. The constructor for the Rhombus class calls the Shape method of the base Shape class: obj@Shape. In the report, click the Shape link in this call.

   The link takes you to the Shape method in the Shape class definition.