function Ai = ex_estab_d_OP07_ex1()
%function Ai = ex_estab_d_OP07_ex1()
% Discrete-time uncertain system used for robust stability evaluation purposes. This systems was
% used in (Oliveira & Peres, IEEE-TAC 2007), Example 1.

A1= [-0.468    0.845
    0.272    -0.423];
A2=[0.825    0.427
    0.299    -0.346];

A3= [-0.744    0.214
    1.242    0.545];

A4=[ 0.330    -1.140
    -0.322    0.309 ];

Ai = [A1 A2 A3 A4];
