I prepared this simple classdef.
classdef myclassA
properties
prop
end
methods
function obj = myclassA(val)
obj.prop = val;
end
function out = horzcat(varargin)
disp('horzcat was invoked');
out = builtin('horzcat',varargin{:});
end
function out = vertcat(varargin)
disp('vertcat was invoked');
out = builtin('vertcat',varargin{:});
end
end
end
Then I performed concatenation of objects.
>> obj1 = myclassA(1);
>> obj2 = myclassA(2);
>> [obj1,obj2]
horzcat was invoked
ans =
1x2 myclassA array with properties:
prop
>> [obj1;obj2]
vertcat was invoked
ans =
2x1 myclassA array with properties:
prop
So far so good. However, when I put the same objects into a structure, I've got rather unexpected behaviours of vertcat.
>> S.obj1 = obj1;
>> S.pbj2 = obj2;
>> [S.obj1,S.obj2]
horzcat was invoked
ans =
1x2 myclassA array with properties:
prop
>> [S.obj1;S.obj2]
horzcat was invoked
horzcat was invoked
vertcat was invoked
ans =
2x1 myclassA array with properties:
prop
Here, the two objects were processed by horzcat twice and then by vertcat once. I wonder if this is expected behaviour (I doubt it) or it is a bug.
When I used vertcat explicitly rather than [a;b], I obtained results in a expected way.
>> vertcat(S.obj1,S.obj2)]
vertcat was invoked
ans =
2x1 myclassA array with properties:
prop
MATLAB R2015b, on Mac OS X El Capitan
