[postgis-tickets] [PostGIS] #3965: KMeans provides less than K clusters

[PostGIS]

#3965: KMeans provides less than K clusters
---------------------+---------------------------
 Reporter:  komzpa   |      Owner:  pramsey
     Type:  defect   |     Status:  new
 Priority:  high     |  Milestone:  PostGIS 2.4.3
Component:  postgis  |    Version:  trunk
 Keywords:           |
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 Clustering 100 distinct points into 100 clusters gets 96 clusters:

 {{{
 select count(distinct cid) from
 (WITH
 points AS (
     SELECT ST_MakePoint(x,y) geom from generate_series(1,5) x,
 generate_series(1,5) y
 )
 SELECT ST_ClusterKMeans(geom, 25) over () AS cid, geom
 FROM points) z;
 }}}

 The larger K is, the bigger losses are.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3965>
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