On 30 April 2017 at 23:34, Jed Brown <j...@jedbrown.org> wrote: > > One reliable, if somewhat expensive, option would be to use > extrapolation similar to TSARKIMEX1BEE.
Somewhat expensive :-) ? > If this feels like reinventing > a wheel using stone tools, it is; we could just add a TSARKIMEX tableau > for Theta with extrapolation. > Oh, I'm not going to touch TSARKIMEX until the TSClone() business gets refactored/cleaned up. But in general, I'm not opposed to your suggestion. > Since Theta is supposed to be an implementation that newcomers use as an > example to learn how TS works, we should try to keep it as clean/simple > as possible. Too late, my friend: * THETA is backing the other two methods BEULER and CN. * We have the DM subdomain/restrict hooks stuff. * We have the adjoint stuff. * And finally, I already added time adaptivity in last release to contribute some extra entropy. so I think THETA abandoned simplicity in favor of features long time ago. > I think it would also be okay to have no error estimator Why? Having support for some sort of adaptivity, that is not default, and based on a cheap estimator seems like a win-win for me... IMHO, practicality beats purity in this case. > -- it seems likely that user implementations may not have an error > estimator (though maybe they should think about it up-front). What did you mean? I'm not following you in these lasts comments... -- Lisandro Dalcin ============ Research Scientist Computer, Electrical and Mathematical Sciences & Engineering (CEMSE) Extreme Computing Research Center (ECRC) King Abdullah University of Science and Technology (KAUST) http://ecrc.kaust.edu.sa/ 4700 King Abdullah University of Science and Technology al-Khawarizmi Bldg (Bldg 1), Office # 0109 Thuwal 23955-6900, Kingdom of Saudi Arabia http://www.kaust.edu.sa Office Phone: +966 12 808-0459