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3

The clustering approach you're describing is referred to as DBSCAN*. (Yes, with an asterisk in the name). There's currently no functionality to do this in PostGIS, though an enhancement request could be made to add it, since it's only a small modification of the DBSCAN algorithm that's already implemented (unreleased). Barring that, DBSCAN* implementations ...


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You would probably be interested in this post: Feature Request - Ability to cluster polygons (Leaflet.markercluster issue #612) You might be interested in Leaflet.Deflate plugin, but be careful when removing the marker (see #580). Another possibility would be to "add" methods getLatLng and setLatLng to your polygons, so that MCG can handle them ...


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I'm pretty sure there's a weird bug here, but it's actually in ST_CollectionHomogenize. I filed a report here: https://trac.osgeo.org/postgis/ticket/3569 As a workaround, you should be able to use ST_CollectionExtract instead of ST_CollectionHomogenize to turn your GeometryCollections into (Multi)Polygons to perform the intersection/containment test.


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You do not seem to be trying the relevant function arguments to test if the eps argument is defined as euclidean distances. That said, it may help to look at the help for the fpc::dbscan implementation as the help is a bit more informative and the model specification/parameters almost identical. The dbscan package implementation is just an optimized version ...


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There are many packages for computing DBSCAN: dbscan, fpc and others. Which do you use ? The unit of EPSG3301 is meter. From Wiki Books: Data Mining Algorithms In R/Clustering/Density-Based Clustering The elements of the database can be classified in two different types: the border points, the points located on the extremities of the cluster, ...


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There are an extremely large number of approaches to clustering, and your question is not answerable, short of writing a textbook describing all possible methods. Therefore, the question I will answer is What information would help me select a clustering method? What is your problem domain? Or, to put it another way, what do the points represent? It could ...



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