Hello, On Fri, Sep 11, 2009 at 11:57 AM, Jonny Taylor <[email protected]> wrote:
> My problem involves a multi-particle system, with complicated inter-particle > forces, but the issue I am having can be seen in a simple overdamped spring > calculation (the derivatives function simply returns dydt[i] = -y[i] * 9.0). How large a value i is? Hopefully not too large. > I use the RK45 stepper, and error control gsl_odeiv_control_y_new(1e-2, 0). I think you really should use relative tolerance as well. Also, you probably want to try tighter tolerances, like 1e-6 or 1e-8 for both. You can try to compare the resulting y with different abstol and reltol to see what is "tight enough". I suggest bsimp as the stepper if your problem is stiff. -- [email protected] http://iki.fi/tuomo.keskitalo _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
