% run_difeq1.m  simple first order
t_range = [0 1];
[t,y] = ode45(@difeq1, t_range, [0]);
size(t);
size(y);
for i=1:20
    j=(i-1.0)/19.0;
    t2(i) = j;
    y2(i) = j*j*j/3.0 + j*j + 3.0*j;
end
plot(t, y, t2, y2, '--');
xlabel('time');
ylabel('y');
title('ODE solution and exact solution');
