function [sys,x0,str,ts] = s_function(t,x,u,flag)
global primary;
switch flag,
case 0,
    [sys,x0,str,ts]=mdlInitializeSizes;
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case 1,
     sys=0;
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 case 3,
     primary=[u;primary(1:14)];
     sys=[0.95 0.08 0.8 0.49 -0.72      0.16 0.19 0.74 -0.20 -0.39      0.5 0.23 0.2 -0.40 0.5 -0.3]*primary

    
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
case { 2, 4, 9 },
    sys = [];
otherwise
    error(['Unhandled flag = ',num2str(flag)]);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function [sys,x0,str,ts]=mdlInitializeSizes
global primary ;
primary=zeros(15,1);


sizes = simsizes;
sizes.NumContStates  = 0;
sizes.NumDiscStates  = 0;
sizes.NumOutputs     = 1;
sizes.NumInputs      = 1;
sizes.DirFeedthrough = 1;
sizes.NumSampleTimes = 1;   % at least one sample time is needed
sys = simsizes(sizes);
x0  = [];
str = [];
ts  = [0 0];