This question is a follow up of another one I have asked a while ago. I have successfully implemented my problem using odeint library and I get the results I expect.
However I would like to give an estimation of the error for the results, obtained by Runge-Kutta method of 4th order. In addition to results obtained by the RK4 method I also have an analytical method to provide solutions.
I have seen another similar question before asking this one. But the treaty of errors in that question is rather rigorous and I don't have expertise in numerical methods. So for me a simple expression based on theory would work fine, and estimation doesn't have to be a very good one.