#361: delta_time when setting up ID with explicit time dependence ------------------------------------------+--------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: ET_2010_11 Keywords: | ------------------------------------------+--------------------------------- In CallInitial, delta_time is used to calculate the time corresponding to the different timelevels (line 399 of Carpet/src/Initialise.cc). At this stage, though, delta_time is always equal to 1, leading to potentially very separated initial-data slices when using init_each_timelevel and an initial-data thorn that uses cctk_time explicitly. Should cctkGH->cctk_delta_time be used here instead?
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: ET_2010_11 Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by eschnett):
Yes, this needs to use cctk_delta_time and not delta_time.
Line 326 in Evolve.cc contains similar code that also loops over time levels for the postregrid bin:
cctkGH->cctk_time -= num_tl * (cctkGH->cctk_delta_time / cctkGH->cctk_timefac);
This could serve as example.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: ET_2011_05 Component: Carpet | Version: ET_2010_11 Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by knarf):
* milestone: => ET_2011_05
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: ET_2011_05 Component: Carpet | Version: ET_2010_11 Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by knarf):
Erik: do you think we should change that before the ET release?
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: ET_2011_05 Component: Carpet | Version: ET_2010_11 Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by eschnett):
At the moment there is no patch, and this is a potentially invasive change. I advise against.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: ET_2011_11 Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by knarf):
* version: ET_2010_11 => * milestone: ET_2011_05 => ET_2011_11
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by hinder):
* milestone: ET_2011_10 =>
Comment:
The same argument holds this time - removing milestone.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by rhaas):
#1098 touched on this since it affected the time stored on levels, but did not change delta_time. It seems as if one has to copy the {{{ for (int ml = 0; ml < mglevels; ++ ml) { // assert (leveltimes.AT(ml).size() == 1); // leveltimes.AT(ml).AT(0) = global_time; for (int rl = 0; rl < reflevels; ++ rl) { CCTK_REAL const dt = delta_time / timereffacts.AT(rl); for (int tl = 0; tl < tt->timelevels; ++ tl) { tt->set_time (ml, rl, tl, global_time - tl * dt); } } } }}} from line 77 in Initialise also after BASEGRID is executed at line 238 of the same file. This is because Time schedules its functions in BaseGrid.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by eschnett):
The effects of thorns Time and CartGrid3D which modify the delta_time and delta_space variables are taken into account in the function CallScheduledFunction. There is a comment that begins with "Manage the time step size."
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by rhaas):
I see. I had not realized that. Thank you. Does this mean this ticket can be closed?
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by eschnett):
We need a test case to ensure things work properly before we can close this. The test case should probably store cctk_time and cctk_delta_time in grid functions, and output these.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by eschnett):
*ping*
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by bentivegna):
How about a test case using an existing initial-data thorn, and outputting all timelevels of a time-dependent exact solution? I'm producing a parameter file right now.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by bentivegna):
Here is a slightly tweaked version of the Kasner parfile that made it to the ET paper. Running it with the current trunk ET gives correct values, for instance, for the metric components. Is this a good test?
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+--------------------------------
Comment (by bentivegna):
Attaching an AMR version of the previous, to show that delta_time is now also correct on all refinement levels.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: review Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by eschnett):
* status: new => review
Comment:
Thanks! Please apply.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: reviewed_ok Priority: minor | Milestone: Component: Carpet | Version: Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by eschnett):
* status: review => reviewed_ok
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: closed Priority: minor | Milestone: Component: Carpet | Version: Resolution: fixed | Keywords: -------------------------------------------+-------------------------------- Changes (by eschnett):
* status: reviewed_ok => closed * resolution: => fixed
Comment:
Added test cases.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: reopened Priority: minor | Milestone: ET_2012_11 Component: Carpet | Version: development version Resolution: | Keywords: -------------------------------------------+-------------------------------- Changes (by bentivegna):
* status: closed => reopened * version: => development version * resolution: fixed => * milestone: => ET_2012_11
Comment:
The added testsuites do not pass on one core, since the data in the repository was obtained on two cores and reflects the corresponding domain decomposition. Please append the lines:
{{{ TEST kasner { NPROCS 2 }
TEST kasner_amr { NPROCS 2 } }}}
to Carpet/Carpet/test/test.ccl.
#361: delta_time when setting up ID with explicit time dependence -------------------------------------------+-------------------------------- Reporter: eloisa.bentivegna@… | Owner: eschnett Type: defect | Status: closed Priority: minor | Milestone: ET_2012_11 Component: Carpet | Version: development version Resolution: fixed | Keywords: -------------------------------------------+-------------------------------- Changes (by eschnett):
* status: reopened => closed * resolution: => fixed
Comment:
Applied.
trac@lists.einsteintoolkit.org
-
Einstein Toolkit