Entity sets - containment and parent-child

[Tim Tautges]

I figured you'd ask that next.  The two that come to mind most readily:

a) I use entity sets to represent geometric topology groupings in the mesh, and parent/child relations between those to 
represent the topological relationships between the original geometric entities.  So, I have "model face" sets, whose 
contents are the mesh owned by that model face, and children corresponding to the bounding model edges.  Instead of 
directly including the mesh faces in a model face set, say I want to preserve a grouping of those faces, e.g. the 
original rectangles of faces composing an "E" or "L" shaped structured mesh.  This would most naturally be stored as 
rectangle sets of faces contained in the model face set.  Similar examples can be made for swept meshes in 3d.

b) Parts in a parallel mesh: parent-child relations can be used to represent the relationship between parts and their 
boundaries.  If you construct a partition using e.g. material sets or model volume sets, then a part set will have both 
child sets (the boundaries of the part) and contained sets (the model volumes composing the part).

- tim

Mark Beall wrote:
> 
> 
> I'd be interested in knowing the various use cases for using entity set 
> containment vs. a parent-child relationship. It seems to me that they 
> are just about identical, so I'm curious when one would use one vs. the 
> other.
> 
> mark
> 
> 

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              Tim Tautges            Argonne National Laboratory
          (tautges at mcs.anl.gov)      (telecommuting from UW-Madison)
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