Hello everyone,
I have a system of 3 non linear equations second order differential.
I'm using radau solving the following system : d/dt (phi) = f(phi)
But i would like to solve the system d²/dt²(phi)= f(phi) instead.
My f(phi) is a three dimensionnal vector with non linear . coupled phi's
For example (i've removed sensitive data and simplified problem)
How would you format D(u,Y) ? I've tried with the other solvers but it didn't solve. I'm stuck with Radau.