From: Garry Petrie (gp_at_europa.com)
Date: Wed Feb 07 2001 - 17:26:33 CET
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devinkouts_at_earthlink.net wrote:
>
> This approach creates the constructs necessary to create and expand
> surveys by either adding new shots directly, or by adding new
> subordinate surveys, or by adding sibling surveys. It further allows
> surveys to be organized under a "super" survey construct, which would
> facilitate the organization of surveys into morphologic representations
> or "cave system" representations.
Devin has taken us back to the original purpose, a discussion how to represent our survey
data. I think, if you want some sort of "grouping" other than a "cave", then that would
have to be done by references back to the original objects. Without realizing it, that is
what we are doing with shot, in an implicit fashion. We write, "A1 A2 5 10 15" as a shot
between A1 and A2, but in doing so have simultaneously defined stations A1 and A2. There
was no check for the existance of these stations. A more fundamental approach might
require use to define a list of unique station names before listing shots!
If you can follow that, then groupings are collections of unique identifiers, not the
data. A grouping might be all those stations in the cave with water, or crickets. A branch
in the cave might be the list of unique survey names. The branch could also be the list of
shots defined by unique station pairs. What we do not want is to embed the actual
measurements of length, bearing, inclination, whatever, in more than one place. For the
gourpings advocates, show me a method that does not repeat data, but allows the objects to
be members of more than one group.
Garry Petrie
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