[R-sig-Geo] bbox

[Tom Gottfried]

assuming your geometry column is 'the_geom': while querying

SELECT ... FROM ... WHERE the_geom @ ST_geomfromtext(...);

with ST_geomfromtext() you can set up your "custom bbox".
But of course you can load everything into R and then use subset() if your data are in a data.frame 
or use over() with e.g. a SpatialPointsDataFrame and a polygon representing your 30x30Km...

Once you have a specific question and some code showing what you actually already tried somebody 
will be able to give you a specific answer.

regards,
Tom

Am 09.11.2011 11:37, schrieb Raffaele Morelli:
> Hi,
>
> once a Postgis layer X is retrieved, how can I juggle with subsets of X?
>
> eg. I am working with bubble plots on a EU dataset but I want to do test it
> only using a 30x30Km in the nearby of Rome and I have no attribute data but
> the value I use for the bubbles. Should I use "subset"? Can I set a kinda
> of custom bbox?
>
> regards
> -r
>
> 	[[alternative HTML version deleted]]
>
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