function res = CGC_2TD_Eqns_VI(t,SOL,DSOL)

global Vp Vi tpti td E Gin di Vg

I = SOL(1); % Insulin variable from SOL vector

G = SOL(2); % Glucose variable from SOL vector

T1 = DSOL(2,1); %tau1

T2 = DSOL(1,2); %tau2

dIdt = f1(T1)-di*I;

dGdt = Gin-f2(G)-f3(G)*f4(T2)+f5(I);

res = [dIdt; dGdt]; % return solution vector

end