On Monday, April 5, 2004, at 10:01 PM, Multiple recipients of list wrote:
From: "Colin Nielsen" <nielsen@myrealbox.com>
Date: Mon Apr 5, 2004 5:13:58 PM America/Phoenix
To: hamish_nospam@yahoo.com
Cc: GRASSLIST@baylor.edu
Subject: [GRASSLIST:3100] Re: Xtent Modelling (wieghted Thieseen)I'm an archaeologist trying to determine possible territories/influence around sites. I want to give certain sites a greater weight of influence than others (such as a capital city vs a small farm). It would be relatively easy to impliment from a programmers point of view. Instead of drawing the boundary at 50% between the sites put it at 70% or whatever based on the wieghting. I was just hoping someone had already done this. Yes/ no?
-Colin
I am also an archaeologist. The short answer is no. No one has produced for GRASS a kind of weighted Voronoi/Thiessen routine that you describe.
I understand what you want to do, and agree that it could be useful. However, I'm not sure that a Voronoi diagram is what you need. Remember, if you use a weighting variable to change the distance at which splits are made between sites, it changes it in all directions. For a small site, the distance might need to be 30% in one direction, but 50% in another. The program would need to work this out. Maybe you could actually draw something this way that completely fills space like Voronoi diagrams, but I worry that there would be trouble with the vertices. Of course, maybe it is just my faulty imagination first thing in the morning.
Michael Barton
______________________________
Michael Barton, Professor & Curator
Department of Anthropology
Arizona State University
Tempe, AZ 85287-2402
USA
voice: 480-965-6262; fax: 480-965-7671