passing handle objects by value

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Hi
I have a class inheriting from the "handle" class, which means (correct me if I'm wrong) it will have reference semantics. I use an instance of the class in a simulation loop and I'd like to save a sanpshot of the object in every iteration. Is there a way to dereference the handle object and pass it by value to store it in a cell array?
Thanks for your replies in advance

Accepted Answer

Steven Lord
Steven Lord on 13 Jul 2021
Have your class inherit from matlab.mixin.Copyable as described on this documentation page.

More Answers (1)

Yongjian Feng
Yongjian Feng on 13 Jul 2021
You don't need to.
classdef aclass < handle
properties
a
end
end
l={}
a = aclass();
a.a = 10;
l{end+1} = a;
a = aclass();
a.a = 20;
l{end+1} = a;
l{1}
l{2}
  2 Comments
mahdi Babayi semiromi
mahdi Babayi semiromi on 13 Jul 2021
Edited: mahdi Babayi semiromi on 13 Jul 2021
Thank you very much for your reply
This is different from the application that I have in mind. my case is like the following:
classdef aClass < handle
properties
a
end
end
aClassInstance = aClass;
l = {};
for i = 1:2
aClassInstance.a = i;
% here I want to save the variable aClassInstance by value, so that I
% have it in its current state. If I just assign it to a cell array,
% like:
l{end+1} = aClassInstance;
% then l{end+1} will only hold a pointer to the variable aClassInstance
% and when I exit the loop, I'll only have access to the latest state
% of the variable
end
Yongjian Feng
Yongjian Feng on 13 Jul 2021
Can you just move the initialization line inside the for loop?
classdef aClass < handle
properties
a
end
end
l = {};
for i = 1:2
aClassInstance = aClass;
aClassInstance.a = i;
% here I want to save the variable aClassInstance by value, so that I
% have it in its current state. If I just assign it to a cell array,
% like:
l{end+1} = aClassInstance;
% then l{end+1} will only hold a pointer to the variable aClassInstance
% and when I exit the loop, I'll only have access to the latest state
% of the variable
end

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