[GRASSLIST:7555] Re: vectorisation - vertex limit?

[Martin Rutzinger]

Hi Markus!

You are right - there is no limit of vector primitives. It's a problem of the
thinning. The raster I used is not thinned properly.
Output of r.to.vect:

update_list:  crowded cell 7H (11,10)
ERROR: cell file is not thinned properly.
       Please run r.thin

So the vectorisation stops at a "crowded cell". Unfortunately  it is not
possible to remove this crowded cells with running r.thin again:

File obj_raster1 -- 21 rows X 26 columns
Bounding box:  l = 2, r = 27, t = 2, b = 22
   Path number 1
        Deleted 0  pixels
thinning completed successfully.
Output file 21 rows X 26 columns
Window 21 rows X 26 columns


Thanks alot
Martin


Zitat von Markus Neteler <neteler at itc.it>:

> Hi Martin,
>
> > The Problem is the vectorisation with r.to.vect: The resulting vector
> (lines) I
> > get is not "finished" when displaying it (bottom part is missing). Further
> > analysis are not possible with this vector - always getting the error:
> > ERROR: Cannot open old vector mwin_vector1 at schlesi on level 2.
>
> No, there is no such limit in the vector model. I just tried
> to split the Spearfish roads map into 1m segments:
>
> GRASS 6.1.cvs (spearfish60): > v.split in=roads out=roads_split length=1
>  100%
> Erzeuge Topologie ...
> 392579 primitives registriert
> Building areas:  100%
> 0 Flächen erstellt
> 0 Inselflächen erstellt
> Füge Inselflächen hinzu:
> Füge Zentroide hinzu: 100%
> Die Topologie wurde erstellt.
> Anzahl von Knoten     :   392430
> Anzahl von Primitives :   392579
> Anzahl von Punkten    :   0
> Anzahl von Linien     :   392579
> Anzahl von Boundaries :   0
> Anzahl von Zentroiden :   0
> Anzahl von Flächen    :   0
> Anzahl von Inseln     :   0
>
> No problem (not even slow :-).
>
> Probably your disk is full and GRASS doesn't report this properly?
>
> Please post the full ourput of r.to.vect to better understand
> the problem.
>
> Markus
>
>