Recent content by dftfunctional

I would like to find a FORTRAN subroutine or a good way to minimize function numerically.So basically my function has 20 variables and I am able to provide analytic form of the first and the second derivative of the function. Basically what I want is: have the form of the function of 20...

Thank you very much, as far as I understood G(f(x)) = G(x) would be equivalent to: ∫ g(f(x)df = ∫g(x)dx And per inspection we could find that one solution is f(x)=x. Empirically I know that there are many solutions to the given equation. Is there a way for "exctracting" f(x) or getting...

Thank you both, As a trained material scientist I am not an expert on ODE. Could you please, therefore provide me more details. If it is separable, how I can proceed to finding a solution considering that there is the composition given in the function?

I have not met differential equations involving the composition functions (also not much literature on it). Assume we know the form of g=g(x), and need to solve the following differential equation, finding f=f(x): (g∘f)f'=g Where g∘f=g(f(x)). Does anybody have a strategy for solving...