I use PostGIS 2.0 and Python API (
GeoAlchemy) to work with it.
I want to convert topological informations (points, lines, faces) from PostGIS tables to topological network (points, lines) to study it with network analyses.
Initial data is a planar graph (shapefile, POLYGON).In PostGIS, my first steps were :
- to create a topological environment (with '
- to convert a shapefile (geometry) into a topological table (topology, with '
Then, I've got :
- a topological extension ('
- a topological schema (called '
- a table with topological lines ('
- a table with topological nodes ('
- a table with topological surface ('
public.es', topological information is in '
I want to study topological surfaces coming from the shapefile as with network analysis, so, surfaces must be considered as nodes of the network.
I know that '
NetworkX', a Python module, permit to read/write network data from/to PostGIS (module '
How can I convert my tables ('
public.es') to a network ? How can I convert polygons ('
public.es.topo') to nodes ?