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% Copyright (c) 2023, Amon Lahr, Simon Muntwiler, Antoine Leeman & Fabian Flürenbrock Institute for Dynamic Systems and Control, ETH Zurich.
%
% All rights reserved.
%
% Please see the LICENSE file that has been included as part of this package.
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classdef LQR
    properties
        K
    end
    
    methods
        %constructor
        function obj = LQR(Q,R,params)
            % YOUR CODE HERE
            % obj.K = ... (save feedback matrix for use in eval function)
            A = params.model.A;
            B = params.model.B;
            [X, L, G] = dare(A,B,Q,R);
            % obj.K = -inv(B'*P_inf*B+R)*B'*P_inf*A;
            obj.K = -G;
        end
        
        function [u, ctrl_info] = eval(obj,x)
            % YOUR CODE HERE
            % u = ...
            u = obj.K*x;
            ctrl_info = struct('ctrl_feas',true);
        end
    end
end