MATLAB: Change struct property values in a class

classhandleMATLABoopstructuresvalue

Hi, I have a problem with using a struct as property of a value class. It seems I cannot change the values of fields (or add new fields).

The simplest example is as follows:

classdef testclass
    properties
        struct_prop=struct;
    end
    methods
        function obj = change_struct_prop(obj, val)
            obj.struct_prop.field1 = val;
        end
    end
end

Trying to change the struct_prop doesn't work:

>> a=testclass;
>> a.change_struct_prop(2);
>> a.struct_prop
ans = 
      field1: []
>>

Is there any way to manipulate a class property that is a struct (without having to define a separate class for it)? Defining the struct_prop fields in the initialisation function didn't help either.

Thanks a lot,

Olf

Best Answer

Replace

    classdef testclass

    classdef testclass < handle

and search the help for "Comparing Handle and Value Classes"

&nbsp

In response to the comment

If a value class, replace

    >> a.change_struct_prop(2);

    >> a = a.change_struct_prop(2);

and read the help on the comparison of value and handle classes

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