[postgis-tickets] [PostGIS] #3697: ST_ConcaveHull does not cover original

[PostGIS]

#3697: ST_ConcaveHull does not cover original
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 Reporter:  rouen           |      Owner:  pramsey
     Type:  defect          |     Status:  new
 Priority:  high            |  Milestone:  PostGIS 2.4.0
Component:  postgis         |    Version:  2.3.x
 Keywords:  ST_ConcaveHull  |
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 I am trying ST_ConcaveHull(geom,0.80) on rather big polygon (~90k points)
 and the result is clearly wrong - it covers maybe half of the original
 polygon. See the original polygon
 https://sygicpublic.blob.core.windows.net/postgis-bug-
 data/fra_polygon_original_image.PNG
 vs. original polygon covered with ST_ConcaveHull(geom,0.80) result:
 https://sygicpublic.blob.core.windows.net/postgis-bug-
 data/fra_polygon_hull_080_image.PNG

 Here are the data (exported as ST_AsText, all srid 4326)
 https://sygicpublic.blob.core.windows.net/postgis-bug-
 data/fra_polygon_original
 https://sygicpublic.blob.core.windows.net/postgis-bug-
 data/fra_polygon_hull_080

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3697>
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