How to modify properties of a Matlab Object [duplicate]

Answer 1

There is an easier way. You only need to overwrite your initial instance s as follows:

s = increment(s,5);

More information in the documentation.

PS: While it is fine to use handle, the way copy function works is different and you should be careful about the way you use it. When you use handle, in fact you are making a new address/reference to an obj

Answer 2

This is similar to this question. In short all you should have to do is inherit from handle class.

Quick example

Contents of file myclass.m

classdef myclass<handle
    properties
        x_array = []
    end
    methods
        function obj=increment(obj,val)
            obj.x_array=[obj.x_array val];
        end
    end
end

Now from the Matlab command prompt, you can do the following

>> s=myclass;
>> s.increment(5)
>> s.increment(6)
>> s

s = 

myclass handle

properties:
    x_array: [5 6]

lists of methods, events, superclasses