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From: Nick C. <vze...@ve...> - 2001-12-02 15:33:33
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On Fri, 2001-11-30 at 21:46, Laszlo Gulyas wrote: > Hi, > > I am not sure I completely understood everything in these mails below > (I have little clue about GIS's), but they certainly sounded interesting. > > Could you explain me at some length what a congruency matrix is? > And I am ashamed to ask, but I am not sure I understand the centroid > thing either... ;-) > > Finally, how is geometry represented in standard gis software? I mean, maybe > we could borrow something from there, too . I am fine with ArrayList, but > who knows... > > On the other hand, I have a couple of less visionary 'proposals', too. All > of these are just quick ideas, so feel free to point out the defects in them. > > - I tend to like the use of ObjectLocation in the multi-occupation grids. > Maybe, we should provide this functionality in all discrete grids. > (I am lacking it when I want to implement moving -- it's OK that I can > grab my neighbors, but it would also be nice if I could grab the > neighborous > cells/locations, too.) I was hoping to do this soon after I wrote the multi-occupancy grid, but I never got around to it. Its still on the list, but feel free to do it yourself, if you have the time :). > > - Also, I would propose to introduce another standard functionality. Something > like DistanceFromTo()... This is because while calculating the distance > on normal > grids is fairly easy, it can get rather complicated in other cases. (The > hexagonal > lattice is one example, but I can also think of a subclass of the normal > 2DGrid, > which contains walls and other obstacles...) > > - Finally, in Node (in the networking library), it would be nice to have > something > like getEdgeTo(Node), which would return the edge that connects the > actual node > to the parameter (or null). I added a some new methods along this line to DefaultNode last thurs. and can certainly add this as well. However, these new methods recognize that a node may have multiple edges to or from another node. For example, a son may have a business link and a family link with his father. Internally there is now a HashMap with nodes as keys and a HashSet of edges as values. Given this, what would be better do you think -- public Iterator getEdgesTo(Node node) or public HashSet getEdgesTo(Node node) Nick -- Nick Collier Social Science Research Computing University of Chicago http://repast.sourceforge.net |