Обсуждение: select points of polygons

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select points of polygons

От
Andreas Gaab
Дата:

Hi there,

 

 

I have polygons with 5 points (left, center, right, top, bottom)

 

Now I would like to select an individual point out of the polygon. Are there any functions to provide this in an readable manner other than:

 

e.g. SELECT replace(split_part(p::text,',(',1),'((','(')::point as point FROM (

SELECT '((0.001329116037,0.007391900417),(0.001371765621,0.1608393682),(0.1502391498,0.00733744679),(0.001500387404,-0.1468751078),(-0.1472653422,0.007425591447))'::polygon as p) as poly

 

è (0.001329116037,0.007391900417)

 

 

Thanks

Andreas

 

 

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SCANLAB AG

Dr. Andreas Simon Gaab

Entwicklung • R & D

 

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Re: select points of polygons

От
Tom Lane
Дата:
Andreas Gaab <A.Gaab@scanlab.de> writes:
> I have polygons with 5 points (left, center, right, top, bottom)

> Now I would like to select an individual point out of the polygon. Are
> there any functions to provide this

Doesn't look like it :-(.  Seems like rather an oversight.
        regards, tom lane