Create a function to declare your filter object as persistent, and initialize the object. You define the object as persistent to maintain the object states between calls.

功能[CorrectedX] = ukfcodegen(output)％将对象声明为持续。persistentobj;ifisempty（obj）% Initialize the object.obj = unscentedKalmanFilter(@vdpStateFcn,@vdpMeasurementFcn,[2;0]); obj.MeasurementNoise = 0.01;end％估计国家。更正=正确（OBJ，输出）;预测（obj）;end

该函数创建一个无声的Kalman滤波器对象，用于在线状态估算具有两个状态和一个输出的范德波尔振荡器。您使用先前编写和保存的状态过渡和测量功能，vdpstatefcn.m和vdpMeasurementFcn.m，并指定两个状态的初始状态值(2, 0). Hereoutputis the measured output data. Save theukfcodegen.m功能on the MATLAB path. Alternatively, you can specify the full path name for this function.

在里面ukfcodegen.m功能, the persistent object is initialized with condition如果Isempty（OBJ）to ensure that the object is initialized only once, when the function is called the first time. Subsequent calls to the function only execute the预测和correct命令更新状态估计。在初始化期间，您指定对象的非义属性，例如StateTransitionFcn（在ukfcodegen.masvdpstatefcn.m) andMeasurementFcn（在ukfcodegen.masvdpMeasurementFcn.m). After that, you can specify only the tunable properties. For more information, seeTunable and Nontunable Object Properties.

在状态过渡和测量功能中，您必须仅使用支持代码生成的命令。金宝app有关这些命令的列表，请参阅支持C/C ++代码生成的功能和对象金宝app(MATLAB Coder). Include the compilation directive%#codegen在里面se functions to indicate that you intend to generate code for the function. Adding this directive instructs the MATLAB Code Analyzer to help you diagnose and fix violations that would result in errors during code generation. For an example, typevdpstatefcn.mat the command line.

Generate C/C++ code and MEX-files using thecodegen(MATLAB Coder)command fromMATLAB Codersoftware.

codegenukfcodegen-args{1}

The syntax-args {1}为您的函数指定参数的示例。该参数设置函数参数的维度和数据类型output作为双重标量。

obj = unscentedKalmanFilter(@vdpStateFcn,@vdpMeasurementFcn,single([2;0]))

codegenukfcodegen-args{{{单（1）}

Use the generated code.

此示例生成用于编译MEX文件的C/C ++代码。要为其他目标生成代码，请参见codegen(MATLAB Coder)在里面MATLAB Coder文档。