function sys=mdlOutputs(t,x,u)

sys=@(x)([4/pi*(cos(x(1))-cos(x(2))+cos(x(3))-cos(x(4))+cos(x(5))-cos(x(6))+cos(x(7))-cos(x(8))+cos(x(9))-cos(x(10))+cos(x(11)))-u(12);

cos(5*x(1))-cos(5*x(2))+cos(5*x(3))-cos(5*x(4))+cos(5*x(5))-cos(5*x(6))+cos(5*x(7))-cos(5*x(8))+cos(5*x(9))-cos(5*x(10))+cos(5*x(11));

cos(7*x(1))-cos(7*x(2))+cos(7*x(3))-cos(7*x(4))+cos(7*x(5))-cos(7*x(6))+cos(7*x(7))-cos(7*x(8))+cos(7*x(9))-cos(7*x(10))+cos(7*x(11));

cos(11*x(1))-cos(11*x(2))+cos(11*x(3))-cos(11*x(4))+cos(11*x(5))-cos(11*x(6))+cos(11*x(7))-cos(11*x(8))+cos(11*x(9))-cos(11*x(10))+cos(11*x(11));

cos(13*x(1))-cos(13*x(2))+cos(13*x(3))-cos(13*x(4))+cos(13*x(5))-cos(13*x(6))+cos(13*x(7))-cos(13*x(8))+cos(13*x(9))-cos(13*x(10))+cos(13*x(11));

cos(17*x(1))-cos(17*x(2))+cos(17*x(3))-cos(17*x(4))+cos(17*x(5))-cos(17*x(6))+cos(17*x(7))-cos(17*x(8))+cos(17*x(9))-cos(17*x(10))+cos(17*x(11));

cos(19*x(1))-cos(19*x(2))+cos(19*x(3))-cos(19*x(4))+cos(19*x(5))-cos(19*x(6))+cos(19*x(7))-cos(19*x(8))+cos(19*x(9))-cos(19*x(10))+cos(19*x(11));

cos(23*x(1))-cos(23*x(2))+cos(23*x(3))-cos(23*x(4))+cos(23*x(5))-cos(23*x(6))+cos(23*x(7))-cos(23*x(8))+cos(23*x(9))-cos(23*x(10))+cos(23*x(11));

cos(25*x(1))-cos(25*x(2))+cos(25*x(3))-cos(25*x(4))+cos(25*x(5))-cos(25*x(6))+cos(25*x(7))-cos(25*x(8))+cos(25*x(9))-cos(25*x(10))+cos(25*x(11));

cos(29*x(1))-cos(29*x(2))+cos(29*x(3))-cos(29*x(4))+cos(29*x(5))-cos(29*x(6))+cos(29*x(7))-cos(29*x(8))+cos(29*x(9))-cos(29*x(10))+cos(29*x(11));

cos(31*x(1))-cos(31*x(2))+cos(31*x(3))-cos(31*x(4))+cos(31*x(5))-cos(31*x(6))+cos(31*x(7))-cos(31*x(8))+cos(31*x(9))-cos(31*x(10))+cos(31*x(11));]);

x=fsolve(sys,[u(1),u(2),u(3),u(4),u(5),u(6),u(7),u(8),u(9),u(10),u(11)]);

sys=x;

end

这里的x是什么？没见你更新状态变量。