
Re: Numerical ODEs
Posted:
May 16, 2013 1:20 PM


On 15052013 21:15, Bart Goddard wrote:
> Pretty much out of my field, (I'll do anything to avoid grading > final exams) but I notice that if you take the > derivative of both side of the DE and substitute, you discover > that f''(x)=2. As I understand, RungeKutta approximates the > second derivative and selfadjusts itself to account.
This works indeed for the ODE f'(x) = 2 sqrt(f(x)), but, more generally, I am interested in ODEs of the type f'(x) = g(f(x)), under the initial condition f(0) = 0 and where g(0) = 0. Then, all I get is:
f''(x) = g'(f(x))*g(f(x))
and I don't see how to proceed from here.
Best regards,
Jose Carlos Santos

