Hello Roland, thank you for the explanation. Actually, I did mean the fifth reflevel (e.g. level "4", counting from 0). My thoughts were the following: if the finest reflevel is the eighth (that is reflevel "7"), at this reflevel the code is executed at each iteration; on reflevel "6", every two iterations; on reflevel "5", every four iterations and on reflevel "4" (on which I get the crash) every eight iterations. So everything should be correct, if I have understood you answer. Thanks again! Cheers, Giulia
Il giorno gio 14 nov 2019 alle ore 18:22 Haas, Roland <[email protected]> ha scritto: > Hello Giulia, > > this has to do with the order of timesteps when doing subcycling in > time (which is what Carpet does). > > cctk_iteration counts RHS evaluations, and is not directly related to > cctk_time ie cctk_time != cctk_iteration * DELTA_TIME. > > Basically the coarsest reflevel has to step first, so that in iteration > 1 (evaluating the RHS for the first time) all reflevels 0..7 step > forward and evaluate the RHS in the EVOL bin. > > In the ANALYSIS bin code only runs once data has been properly > restricted from the finer ones etc. Which happens at slightly different > times than EVOL. > > The net result is that in *EVOL* a function runs in refinement levels > whenever (cctk_iteration - 1) % reflevel_every == 0 while in *ANALYSIS* > it is cctk_iteration % reflevel_every == 0. The strange rule in EVOL > comes from asking "was the last iteration one where the timelevel was > aligned so that I now need to compute a new RHS"? > > Thus 473 - 1 = 472 which is evenly divided by 8. NB you say reflevel 4, > but do you mean the fourth reflevel (which is level "3" since they > count from "0")? > > Yours, > Roland > > > Hi all, > > I am using GRHydro in running a simulation, and I get a crash in > > Con2Prim at iteration 473 on reflevel 4. Given that I have set 8 > > refinement levels, I'm wondering why Con2Prim is being executed at > > iteration 473 on this reflevel: shouldn't it be executed only at an > > iteration which is a multiple of 8? Maybe I'm missing something > > fundamental. Thank you, > > Cheers, > > Giulia Crotti > > > -- > My email is as private as my paper mail. I therefore support encrypting > and signing email messages. Get my PGP key from http://pgp.mit.edu . >
_______________________________________________ Users mailing list [email protected] http://lists.einsteintoolkit.org/mailman/listinfo/users
