MATLAB: How to properly overload horzcat and vertcat

classhorzcatoopoperator overloadingvertcat

Hi, im having some trouble overloading horzcat/vertcat for my class with 2 properties:
classdef myClass
    properties
        a
        b
    end
    methods
        function obj = myClass(u,v)
            obj.a = u;
            obj.b = v;
        end
        function out = horzcat(varargin)
            ...
        end
    end
end
As a result of the concatenation i want to achieve just the concatenations of the two proprieties, for example concatenating those objects:
x = myClass(2,3);
y = myClass(4,5);
ConcArray = [x,y];
i would like to have as a result a single object with as properties the concatenation of each property. Basically having the equivalent of:
EquivalentObj = myClass([2,4],[3,5])
I came up with this solution:
function out = horzcat(varargin)
    
    n = length(varargin);
    aProp = [];
    bProp = [];
    
    for i = 1 : n
        var = varargin{i};
        aProp = [aProp var.a];
        bProp = [bProp var.b];
    end
    out = myClass(aProp,bProp);
end
but it looks really bad since i couldn't preallocate the concatenating arrays, im using a for loop and in each loop im using standard horzcat recursively.
Any ideas on how to improve that ? Thank you in advance.

Best Answer

This looks more Matlabish, but whether it's better ...
classdef    myClass
    properties
        a@double
        b@double
    end
    methods
        function obj = myClass(u,v)
            obj.a = u;
            obj.b = v;
        end
        function out = horzcat(varargin)
            obj = cat( 2, varargin{:} );
            as  = [ obj.a ];
            bs  = [ obj.b ];
            out = myClass( as, bs );
        end
    end
end
Test
%%
x = myClass(2,3);
y = myClass(4,5);
ConcArray = [x,y]
outputs
ConcArray = 
  myClass with properties:
    a: [2 4]
    b: [3 5]
>>
and try @Walter's expression
>> [myClass(2,3), myClass(11, tf([17 0], [1 9]))]
Error setting property 'b' of class 'myClass':
Value must be 'double'.
Error in myClass (line 9)
            obj.b = v;
"I couldn't preallocate" why not just
    n = length(varargin);
    aProp = nan(1,n);
    bProb = nan(1,n);
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