[ET Trac] [Einstein Toolkit] #419: CarpetRegrid2 sets up grids which are not consistent

[Einstein Toolkit]

#419: CarpetRegrid2 sets up grids which are not consistent
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  Reporter:  knarf   |       Owner:  eschnett
      Type:  defect  |      Status:  review  
  Priority:  minor   |   Milestone:          
 Component:  Carpet  |     Version:          
Resolution:          |    Keywords:          
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Comment (by rhaas):

 Replying to [comment:6 eschnett]:
 > The attached parameter file tov_16.par has a problem; the simulation
 domain is too small. In other words, with buffer zones, the first refined
 level is too large. Enlarging the domain from 256 to 288 cures this
 problem, and the volume is then correct.

 Adding:
 {{{
 CarpetRegrid2::min_distance = 0
 }}}
 also fixes the issue. Is there a reason that CarpetRegrid2 defaults to
 enforcing a min_distance of 4 grid points between the refinement levels? I
 found this a surprising (and so did apparently Frank) when I first ran
 into it (in the WeylScal4 testsuite)? It seems strange that CarpetRegrid2
 would modify the grid setup the user describe if this is not required to
 produce a well nested / standards conforming grid structure. If this is
 parameter is new and could also be set to default to zero, is it to late
 to bring up the suggestion to have min_distance's default changed 0?

-- 
Ticket URL: <https://trac.einsteintoolkit.org/ticket/419#comment:9>
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