[postgis-users] Sample - Points into Polygons

[Vispo Leblanc]

Hello PostGIS users,



I have one table with thousand of polygons and another one with million of
points. I would like to select all the points that are within the polygons,
BUT I just want a sample of the data. Let me explain.



Let’s say I have a polygon of 1,000 square meter with 60 points, ideally I
would like to take only 1 points. But if the polygon is 10,000 square meter
with 600 points then ideally I would take only 10 points. Also, in a
perfect world, I would only select a sample of points that are spread out
enough to be representative of the polygons. Let’s take the 10,000 square
meters polygon for example, I would only select 10 points that are
everywhere in the polygon and not 10 points that are within 10 meters of
each other’s.



I draw the following diagram to explain:


[image: image.png]

Please let me know if you have any ideas or functions I can use to solve my
problem.



Thank you :-)

Vispo
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