I understand you are encountering issues related to using enumerated types in Simulink for conditional logic and the other regarding "classdef" use.
Using Enumerated Data for Conditions in Simulink
To implement conditional logic using custom data types, you first need to define the enumeration and then use it in your model.
1. Defining the Enumerated Type
The best practice is to define your enumeration in its own ".m" file. The name of the file must match the name of your enumeration class. For this to work with Simulink, the class should inherit from "Simulink.IntEnumType".
For example, to create an enumeration for traffic light states, create a file named "TrafficLight.m" with the following code:
classdef TrafficLight < Simulink.IntEnumType
enumeration
Red(0)
Yellow(1)
Green(2)
end
end
Ensure this file is saved on the MATLAB path so Simulink can find it.
2. Implementing Conditional Logic
In your Simulink model, you can now use this type to control a "Switch Case" block.
- Use an "Enumerated Constant" block to create a signal of your new type. Set its Value parameter to one of the enumeration members, for example, TrafficLight.Red.
- Connect this signal to the input of a "Switch Case" block. The block will automatically create output ports for each member of the enumeration (Red, Yellow, Green), allowing you to build different logic for each state.
Please use the following command to refer to the documentation for more information on Using Enumerated Data in Simulink Models:
doc use-enumerated-data-in-simulink-models
"classdef is illegal use of keyword" Error
This error message indicates that MATLAB is trying to interpret your class definition file as a script.
In MATLAB, a file containing a class definition must begin with the "classdef" keyword. It can be preceded only by comments or whitespace. If any other executable code (like "clc", "clear all", or any variable assignment) comes before the "classdef" line, MATLAB will treat the file as a script, which cannot contain class definitions.
To fix this, simply open your .m file and remove any commands that appear before the "classdef" line.
