I had a brief look at the tides and spokes. My impression was that it was well presented.
I am curious on the large expressions for which you used subexpression elimination and wonder if you have tried `lambdify(..., cse=True)` on them with any favorable results. I look forward to spending some more time looking at what you have done. Best regards, /c On Wednesday, September 29, 2021 at 4:23:17 PM UTC-5 [email protected] wrote: > Hello, > > we just released the latest version of our Taylor integrator heyoka.py: > > https://github.com/bluescarni/heyoka.py > > heyoka.py is an implementation of Taylor's method for the numerical > integration of systems of ODEs based on automatic differentiation and > just-in-time compilation via LLVM. > > Current features include: > > - support for both double-precision and extended-precision floating-point > types, > - the ability to maintain machine precision accuracy over tens of billions > of timesteps, > - high-precision zero-cost dense output, > - accurate and reliable event detection, > - excellent performance, > - batch mode integration to harness the power of modern SIMD instruction > sets. > > heyoka.py needs to represent the ODEs symbolically in order to apply the > automatic differentiation rules necessary for an efficient implementation > of Taylor's method. For this purpose, heyoka.py uses its own expression > system, but in recent versions we added the ability to convert heyoka.py's > symbolic expressions to/from SymPy. Here's a simple example of > interoperability between heyoka.py and SymPy: > > https://bluescarni.github.io/heyoka.py/notebooks/sympy_interop.html > > Here instead is a non-trivial example where the equations of motion are > formulated via SymPy's classical mechanics module and then integrated via > heyoka.py: > > https://bluescarni.github.io/heyoka.py/notebooks/tides_spokes.html > > This second example also shows how the common subexpression elimination > capabilities of heyoka.py were able to drastically simplify highly-complex > Lagrangian equations. > > As a long-time observer/user of SymPy, I thought that other SymPy users > might find this project interesting. I am also looking for feedback on our > SymPy conversions facilities, as this is my first time digging into the > SymPy expression system internals. > > Thanks and kind regards, > > Francesco > -- 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/d607d3af-4b4d-4e10-a291-e3790df8bc05n%40googlegroups.com.
