function [sys,x0,str,ts]=Di(t,x,u,flag)
switch flag,
case 0,
    [sys,x0,str,ts]=mdlInitializeSizes;
case 3,
    sys=mdlOutputs(t,x,u);
case{1,2,4,9}
    sys=[];
otherwise
    error(['Unhandled flag =',num2str(flag)]);
end
function [sys,x0,str,ts]=mdlInitializeSizes
sizes=simsizes;
sizes.NumContStates=0;
sizes.NumDiscStates=0;
sizes.NumOutputs=4;
sizes.NumInputs=8;
sizes.DirFeedthrough=1;
sizes.NumSampleTimes=1;
sys=simsizes(sizes);
x0=[];
str=[];
ts=[0,0];
function sys=mdlOutputs(t,x,u)
sys=[u(2)-u(1),u(4)-u(3),u(6)-u(5),u(8)-u(7)]/(pi/4);
end