ODE45求解

求如下方程，编写程序如下，求指点哪里的问题

其中R,χ1,χ2,εp,σ为待求变量，a1,c1,a2,c2,b,Q,Z,n,k,E是固定且可知的

function dydt=chaboche4_differential_equation(t,y）

dydt=[(max((abs(y(5)-(y(2)+y(3)))-y(4)-x0(9)),0)/x0(5))^x0(6)*sign(y(5)-(y(2)+y(3)));…

x0(2)*(x0(1)*sign(y(5)-(y(2)+y(3)))-y(2)abs(sign(y(5)-(y(2)+y(3)))))(abs(max((abs(y(5)-(y(2)+y(3)))-y(4)-x0(9)),0)/x0(5)))^x0(6);…

x0(4)*(x0(3)*sign(y(5)-(y(2)+y(3)))-y(3)abs(sign(y(5)-(y(2)+y(3)))))(abs(max((abs(y(5)-(y(2)+y(3)))-y(4)-x0(9)),0)/x0(5)))^x0(6);…

x0(7)*(x0(8)-y(4))*abs((max((abs(y(5)-(y(2)+y(3 )))-y(4)-x0(9)),0)/x0(5)).^x0(6)*sign(y(5)-(y(2)+y(3))));…

x0(10)*(0.0002-(max((abs(y(5)-(y(2)+y(3)))-y(4)-x0(9)),0)/x0(5))^x0(6)*sign(y(5)-(y(2)+y(3))))];

end

运行程序

tspan=[0 6000];

y0=[0,0,0,0,0];

x0=[10,1000,10,200,6.76,19.96,2.76,10.37,87.01,101000];

[t,y]=ode45(‘chaboche4_differential_equation’,tspan,y0,x0);

figure;

plot(t,y(2),’-o’)