Dear all,

It was originally from @ivanpribec reply, about Fortran delay differential equations, which is great!

I am checking S. Thompson’s DDE_solver and DKLAG6 solver,

https://www.radford.edu/~thompson/ffddes/index.html

Unfortunately, it seems Thompson’s website is no longer available.

After searching github, I do notice below there are two repos contain Tompson’s DDE solver,

but Thompson’s DKLAG6 solver is still missing.

As both @Arjen and @ivanpribec pointed out, DDE_solver f90 come after DKLAG6, so perhaps no need for DKLAG6 anymore. So I do not know what should be the title of my thread, LOL.

**Anyway, what Delay Differential Equations Solver(DDE) solver do you use?**

**Besides Thompson’s DDE_SOLVER, is Hairer’s solver good enough?**

Another irrelevant question,

**guys, if you learned the methods of Thompson and/or Hairer’s, and you write your own modern Fortran version of DDE and/or ODE solver. Is there a chance that your modern version can be significantly faster than code of Thompson and Hairer’s?**

Thank you very much indeed in advance!

PS.

There is another DDE solver called DDVERK90 by Hossein Zivari Piran,

https://www.cs.toronto.edu/~hzp/index_files/software.html