For your second question, you could rewrite your static method to use persistent variables, like below, and that should work
classdef SingletonClass < handle
properties (Access = protected)
data (1,1) double = 5;
end
methods (Access = private)
function this = SingletonClass()
% Constructor
end
end
methods (Static, Access = public)
function obj = Instance()
% Get singleton instance
persistent instance
if isempty(instance)
instance = SingletonClass();
end
obj = instance;
end
end
methods (Access = public)
function out = test(this, val)
% Test code
out = this.data + val;
end
end
end
