On Sat, 13 Mar 2021 at 14:27, Naveen Saisreenivas Thota <[email protected]> wrote: > > Hi all, > > I wanted to discuss the project "Integrating factors for second order ODEs". > First off, is the paper too big for a GSoC project this year since the time > limit is reduced? If not, even parts of the paper can be implemented. I have > already gone through the paper, and I have some doubts regarding it.
It is polite to give links to what you are referring to rather than expecting others to go look it up: https://github.com/sympy/sympy/wiki/GSoC-Ideas#other-ode-ideas The paper is "Integrating factors for second order ODEs" by E.S. Cheb-Terrab and A.D. Roche and is linked to here: https://drive.google.com/file/d/1-XktJVEzpRK9nOlaMjE7arEgMgGlV_sN/view I have just looked very briefly at the paper. Not having read it I can't answer your detailed questions. What I can say is that the algorithm looks fairly complicated and the kinds of ODEs that it can solve are not that common compared to other cases that dsolve is unable to solve. There are simpler and more useful algorithms that have not yet been implemented in sympy. In particular the Kovacic algorithm gives solutions for a useful and commonly occurring class of ODEs: https://www.sciencedirect.com/science/article/pii/S0747717186800104 The Kovacic algorithm can find any Liouvillian solution to any 2nd order linear ODE with rational function coefficients. This makes it somewhat like the Risch algorithm in that it can prove the non-existence of solutions from a given class of functions. (It is based on the same theory as the Risch algorithm but is much simpler.) Oscar -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAHVvXxRkDMAOSeeWT4GKFJe77ESBadr80fNy6e2JxJdvxXGA0g%40mail.gmail.com.
