[postgis-users] Centroid out a list of points

[Pedro Doria Meunier]

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Thank you Nicklas for your advice! That actually accomplishes it with
a notable exception:

Altough the table has a gist index on the geom column the query is
always executed in Seq Scan mode...

I ask the gurus which fx is causing this, st_centroid or st_collect ?

BR,

Pedro Doria Meunier
GSM: +351 96 17 20 188
Skype: pdoriam
 



nicklas.aven at jordogskog.no wrote:
> select st_centroid(st_collect(the_geom)) from thetable group by
> some_groupe_attribute
>
> if you want the centroid of all points you just leave the
> group-part. then it groups everything by default.
>
> /Nicklas
>
>
> 2009-06-12 Pedro Doria Meunier wrote:
>
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>> Hi all,
>>
>> I'm trying to get the centroid of a list of points and I'm a bit
>> unsure on how to proceed. The first thing that came to mind was
>> converting the list of points to a polygon but that wouldn't
>> always return a "clean" polygon (e.g. inner points) ... Any
>> thoughts would be greatly appreciated :)
>>
>> BR, - --
>>
>> Pedro Doria Meunier GSM: +351 96 17 20 188 Skype: pdoriam
>>
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