Because to attain the solution near t_0 and t_{\text{final}} rk45 needs to reduce time step aggressively, while AM doesn’t have to because it can enlist higher-order to reduce truncation error.
Because to attain the solution near t_0 and t_{\text{final}} rk45 needs to reduce time step aggressively, while AM doesn’t have to because it can enlist higher-order to reduce truncation error.