copy a dynamicprops object by value

4 views (last 30 days)
Yvan Lengwiler
Yvan Lengwiler on 26 Jan 2015
Answered: Tejas on 20 Sep 2024
I've created a class that is a subclass of dynamicprops,
classdef myclass < dynamicprops
When I create an instance of this
c = myclass
and then copy this
d = c
then d and c refer to the same underlying object. Therefore, whenever I change a property of c, the corresponding property of d changes as well (because c and d really refer to the same thing).
Question 1. How can I make a "real" independent copy of c?
Question 2. Alternatively, can I adapt the class definition so that it will be copied "by value" and not "by reference" ?
Thanks for your help.

Answers (1)

Tejas
Tejas on 20 Sep 2024
Hello Yvan,
The 'dynamicprops' class is a subclass of the 'handle' class. This means that when 'myclass' inherits from 'dynamicprops', one object is copied to another by reference.
To ensure objects are copied by value, consider the following workaround:
This approach will create an independent copy of the original object. This workaround can also be incorporated into the class definition of 'myclass' by creating a function that takes an object as an input, performs the above steps, and returns the new object.
Below is an example code snippet demonstrating how this can be achieved:
classdef myclass < dynamicprops
methods
function newObj = copy(obj)
save('temp.mat','obj');
matFile = load('temp.mat');
newObj = matFile.obj;
end
end
end
The following syntax can then be used to create an independent copy of an object:
d = c.copy();
Below is a screenshot of the expected output:

Categories

Find more on Construct and Work with Object Arrays in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!