vectors: lines to polygons

[Michel Wurtz - ENGEES/CEREG]

Juan Bañuls wrote:
>
> Labelizing all the areas doesn't help. It seems to me that it doesn't works
> because v.support's algorithm is not able to recognize the polygons
> contained in the map.
> 

When v.support doesn't recognize polygons, it is generaly because
you have some lines that doesn't connect in your file. With v.support,
you can identify polygons not closed or lines not connected.

It appears also that if you have a *very* little line alone, th polygon
cannot be closed :

BAAAAAAAAAAAAAAAD
B              CD
 B            C D
  BBBBBBBBB     D
           BBBDDD

The line marked 'C' must be either deleted, either changed in 'L' type
(only 'A' type line are used for polygon topology)

-- 
Michel Wurtz    ENGEES - CEREG
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