Thanks Remi,
I thought that but I have no starting/ending points. St_StartPoint and
St_EndPoint are not working with MultiLinestrings
I'll give it some more intense thought. :)
Cheers.
*Toni Hernández Vallès*
Servei de Sistemes d'Informació Geogràfica i Teledetecció
-
Universitat de Girona
*SIGTE*
-
Pl. Ferrater Mora 1
17071 Girona
Tel +34 972 418 039 (7026 intern)
t...@sigte.udg.edu <mailto:t...@sigte.udg.edu>
http://www.sigte.udg.edu
Twitter http://twitter.com/SIGTE_UDG
On 08/06/2015 17:45, Rémi Cura wrote:
if you have start and end point of geom B,
you can get the river path with a shortest path method (one liner
using python, can be done in few hours using plpgsql).
The idea is that you cut your geom into segments(pairs of points)
, the length of the segment is the weight of this edge
, and you know which segment is connected to which segment (adjacency
graph).
Then you use Networkx
<http://networkx.lanl.gov/reference/generated/networkx.algorithms.shortest_paths.generic.shortest_path.html#networkx.algorithms.shortest_paths.generic.shortest_path>shortest
path distance.
Else,
you are up to use some nasty workaround I suppose (playing with
buffers on your original river surface, testing which segment
intersects etc. ).
I tried that but it ends up being more work (and more corner cases)
than doing the things properly (in my experience).
Cheers,
Rémi-C
2015-06-08 16:42 GMT+02:00 toni hernández <t...@sigte.udg.edu
<mailto:t...@sigte.udg.edu>>:
Hi everyone,
I have a multilinestring with a river and all its afluents as you
can see in this image
http://sigserver4.udg.edu/apps/geometries.png
I got geometry A using St_StraithSkeleton.
Is there a way to go from geometry A to geometry B??
Maybe something similar to SmoothLine???
--
*Toni Hernández Vallès*
Servei de Sistemes d'Informació Geogràfica i Teledetecció
-
Universitat de Girona
*SIGTE*
-
Pl. Ferrater Mora 1
17071 Girona
Tel +34 972 418 039 (7026 intern)
t...@sigte.udg.edu <mailto:t...@sigte.udg.edu>
http://www.sigte.udg.edu
Twitter http://twitter.com/SIGTE_UDG
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