[postgis-devel] [PostGIS] #174: Point Clustering Utility Trigger

[PostGIS]

#174: Point Clustering Utility Trigger
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 Reporter:  pramsey      |       Owner:  pramsey       
     Type:  enhancement  |      Status:  new           
 Priority:  medium       |   Milestone:  PostGIS Future
Component:  postgis      |     Version:                
 Keywords:               |  
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Changes (by brian252):

 * cc: brian252 (added)


Comment:

 I've tried SnapToGrid in the past and it doesn't look impressive.

 I wrote up an implementation of k-means clustering.  It's not perfect, but
 it will work for web-maps.  It clustered 22,000 points
 (tiger.tl_2009_51_cty.pointlm) in about 30 seconds.

 The algorithm isn't complicated, but i'm not sure how to set up the
 mechanics of creating this auxiliary table.  It currently runs for n
 iterations.  It would be better to run the clustering until the clusters
 move less than some delta.

 It's hosted here http://brian.derocher.org/?Page=project&Id=104201

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/174#comment:4>
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