[postgis-users] Area calculation

[David TECHER]

if you want to know the number of geometries you have
for a multipolygon with holes do

select numgeometries(the_geom) from yourt_able

Suppose it is N

then 

for j=1 until j=N do

  select aread(geometryn(the_geom,j)) from your_table

end

add all the surfaces you find











 --- Dirk Geschwandtner <dg at mapmedia.de> a écrit : >
Hello List,
> I nee to calculate the areas of
> swiss-cheese-polygons without the holes in 
> postgis.
> 
> I tried convexhull, but this not always returns the
> correct results, the 
> area is slighty bigger
> than the area of the original.
> 
> Has anybody got a better idea?
> 
> TIA,
> 	Dirk
> 
> _______________________________________________
> postgis-users mailing list
> postgis-users at postgis.refractions.net
>
http://postgis.refractions.net/mailman/listinfo/postgis-users 

_________________________________________________________________
Do You Yahoo!? -- Une adresse @yahoo.fr gratuite et en français !
Yahoo! Mail : http://fr.mail.yahoo.com