[GRASS-user] importing .dgn files in grass

[Juan Miguel Garijo]

--- nishith datta <nkdiitd2002 at gmail.com> escribió:

> Thanks juan,
> You were a gr8 help.
> But one problem some of the layers have point & line
> both types of objects.
> How do I select one of the two and discrad the
> other....?
> Let us say the airfield layer has the points where
> the airfield are and the
> symbol which is
> made of arcs and has an aeroplane drawn. I donot
> want the symbol so I wish
> to extract only
> the points. I use v.extract. But how do I know which
> layer has what info and
> it is in what form - line, point or poly. If I donot
> know that how can I
> extract the relevant info.? Is it so that dgn files
> have layers by some
> protocol . where can I find that info.
> Sorry to bother you , but thought you may help me
> out.
> Thanks once again.
> nishith
> 

In the dgns I use always I find a combination of 2
fields of those 
Type : 
Level : 
GraphicGro : 
ColorIndex : 
Weight :
Style : 
EntityNum : 
MSLink : 
Text : 
enough for discrimination with clause "where Level=X
AND OtherField=Y" I d'ont know in yours.
The patient text with v.external is the only way I
know to look after the patterns used in map's
symbology.
I've never used the 'minimun size of areas to be
imported' in order to discard symbols. May be...
nor the flags 'point', 'boundary',...
Good luck,  dgns are funny

NOTE for Gerald Nelson:
I d'ont feel able to write FAQ because my English and
GRASS skills.
I have a set of exercises in Spanish of a course of
GIS with GRASS starting with dgns with copyright. If
someone is interested I can send it.




	
	
		
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