解决从超类继承时实现 matlab.system 的问题

Question

我正在尝试将 matlab class 实现到 simulink MATLABSystem 中。当我实现 superclass 时，模拟工作正常，但是使用 subclass 我得到以下错误：

》Simulink无法自动推断[=27=的输出信号属性]。Simulink使用代码生成技术从System object中自动判断输出信号属性。System object 'subclass' 包含不支持代码生成的代码。错误是 '未定义函数或变量 'obj'。对局部变量的第一次赋值决定了它的 class。' MATLAB System 模块 'subclassSystem' 发生错误。请参阅文件 'superclass.m' 中的第 29 行第 28 列。在大小传播阶段检测到错误。"

我在下面的代码中注释了这一行

我是否必须指定其他内容？

这里是子class定义：

classdef subclass < superclass
    properties(Access = protected) % These variables must be initialised. Here or in the setupImpl function
    end

    methods (Access=protected)
        function resetImpl(obj)
        end

        %% Common functions
        function setupImpl(obj)
            % Perform one-time calculations, such as computing constants
            setupImpl@superclass();
            %obj.initFilter(obj.sampleTime, obj.delta_i, obj.delta_d, obj.g_mps2, obj.q0, obj.b_w0, obj.sigma_2_w, obj.sigma_2_a, obj.sigma_2_b_w, obj.sigma_2_yaw)
        end

        function attitude = stepImpl(obj,u, y)
            % Implement algorithm.
            attitude = 5;
        end
    end

    methods

        % Constructor must be empty for matlab.System. In Matlab call
        % initFilter after the object was created. In simulink setupImpl()
        % will be called
        function obj = subclass()
            obj@superclass();
        end
    end

end

这里是超级class定义：

classdef superclass < matlab.System


    % These variables must be initialized in the simulink model
    properties
        sigma_2_w;
        sigma_2_a;
        sigma_2_b_w;
        sigma_2_yaw;
    end

    properties(Access = protected) % These variables must be initialised. Here or in the setupImpl function
        R;
        Q;
    end

    methods (Access = protected)

        function resetImpl(obj)
        end

        %% Common functions
        function setupImpl(obj)
            % Perform one-time calculations, such as computing constants
            obj.Q  = diag([obj.sigma_2_w',obj.sigma_2_b_w']); % this is line 29
            obj.R = diag([obj.sigma_2_a',obj.sigma_2_yaw']); 
        end

        function attitude = stepImpl(obj,u, y)
            % Implement algorithm.
            attitude = 5;
        end
    end

    methods

        % Constructor must be empty for matlab.System. In Matlab call
        % initFilter after the object was created. In simulink setupImpl()
        % will be called
        function obj = superclass()
             % Support name-value pair arguments when constructing object
        end
    end
end

Answer 1

我发现了错误。在子类的 setupImpl 函数中，我不得不以 obj 作为参数调用超类的 setupImpl：

setupImpl@Superclass(obj);

这是我的构造函数。这里我没有使用obj作为return值

function obj = Subclass()
    obj = obj@Superclass();
end

解决从超类继承时实现 matlab.system 的问题

Troubleshoot with implementing matlab.system from when inheriting from superclass

matlab

code-generation

simulink