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
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