Re: graphs

• To: Manuel Simoni <manuels@xxxxxxxxxxxxxxxxxxxxx>
• Subject: Re: graphs
• From: Oscar Stiffelman <oscar@xxxxxxxxxxxx>
• Date: Thu, 24 Jan 2002 15:16:40 -0800 (PST)

I am not a visad expert, but I recommend not coupling the graph (adjacency
matrix or adjacency list) data structure to the existing VisAD data
structures, until it comes time for the embedding in R^2 or R^3 (which is
the function performed by the layout algorithm).  It will be easier for
people to import graph data into whatever you design if you keep the
topology encoding and the cartesian embedding conceptually orthogonal to
each other.  It is also a natural interface boundary to make it easier to
plug in layout algorithms that can work with arbitrary underlying topology
encodings.

I am curious if the rest of the visad community (especially those more
familiar with the visad themes and design) agrees with this assessment.
I am also curious if this is the sort of datatype that the main visad team
feels is appropriate to integrate into the overall framework.

-- Oscar Stiffelman



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On Thu, 24 Jan 2002, Manuel Simoni wrote:

> Oscar,
>
> > Have you chosen a graph data structure yet?  I assume you will use some
> > kind of adjacency list representation to support sparse directed graphs,
>
> I am currently testing with hand-made *positional* data, and do not have an
> underlying graph structure yet. I feel that the underlying structure in any
> case will go thru a heavy adaption process to visad math and display types,
> so this is not a problem.
>
> > but I am curious if you have chosen the data types for the node and edge
> > labels,
>
> If you are talking about a visad MathType structure for them, no. I have
> tried out two today, but both had problems. If you have suggestions, let me
> know.
>
> > and if you will be using primitives or objects.
>
> What primitives and objects do you mean?
>
> Manuel
>
>
>

• Follow-Ups:
  • Re: graphs (layouting-related)
    • From: Manuel Simoni
  • Re: graphs
    • From: From: Bill Hibbard <hibbard@xxxxxxxxxxxxxxxxx>

• References:
  • Re: graphs
    • From: Manuel Simoni