[GRASS-user] Remove island

[Yves Jacolin]

Hi,
After a vectorisation from a raster obtained by the r.los function, I get 
polygon whom own some island inside them. I would like to remove this island?
Here :http://yjacolin.gloobe.org/problem.htm, three pictures :
 1/ what I expect to
 2/ What I get

I obtain the first picture by using sql resquest (display only value=1).

Do you know where the problem came from ?
Thanks to any tips ! It seems to me that I saw something about this in the 
past in this list but ... :-(

Y.
-- 
Yves Jacolin
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http://yjacolin.gloobe.org
http://softlibre.gloobe.org