Hierarchies + Topic Map Types

  • Alex Shapiro wrote:
    > >    - categorizing nodes (aka "Type" in TopicMaps)
    > Tell me more about this categorizing.

    Victor wrote:

    I think it is a very powerful concept in the TopicMap spec. Each topic can have a "Type" (even more than one, but I think one should be enough). This type is also a topic in its own. These types are used to group/categorize topics. You might want to filter by these types (on the same line of thought, associations have roles).


    I like this idea of Types.  Would it be possible to think of them as parents in a hierarchy?

    In the flat structure that currently exists, every node has a set of associated nodes, which are attached to it by directed edges.

    It seems to me that we could represent Types, by dividing the set of associated nodes into simple associations, and parents.  (Depending on the amount of redudancy we want to have, there could also be children).  A node could have multiple parents just like a topic could have multiple types.

    Basically, it's the same data structure as that of theBrain.  We have a hierarchy coexisting with crossreff. 

    It seems that this type of structure has the maximum simplicity, and therefore the greatest flexibility.


    • Victor Volle
      Victor Volle

      > Would it be possible to think of them as parents in a hierarchy?

      Yes, but that would really alter the meaning of "type" in topic maps.
      A type and the node referencing it are in a class/instance relationship, so they are
      in semantically different levels (difficult to express in englich).
      I think that this does not map very well to a parent/child relationship.
      I would prefer adding a parent/child and a crossref relationship in touchgraph.

      I would use types to filter nodes, to display nodes of different type in another
      color, to refine searches etc. I generally even would not display type nodes (but
      add a switch that makes them appear).