[Help-gsl] Solving coupled ode's with gsl_odeiv

[Peter . Milner]

Hi,
I have a set of 15 coupled ode's which I am solving with
gsl_odeiv_step_rk4. When I solve these ode's in Maple it only takes a
second for a couple of time steps. However using the gsl_odeiv_step_rk4
method it takes about 4 minutes. The initial conditions I have vary
between zero and 6 million.

I have been using h=1e^-6 and control =
gsl_odeiv_control_y_new(1*e^-6,1*e^-6).

I have used this method quite before with 77 coupled ode's and not had
such a problem. In that case the initial conditions were all under 100.

I have tried each of the rk stepping functions, with rkck being the
quickest but still taking more than three minutes.

Is there anything I can do to increase the speed for large initial
conditions?

Thanks for your time,
Pete