# Tagged Questions

47 views

### How to calculate the shortest distance for multiple source and targets using PgRouting?

I have a table with points and a road network which includes driveways (where you enter the highway). I want to find the point which is closest to a driveway. So I was thinking I can calculate the ...
134 views

### How to connect points (bus stops), which don't lie on the lines (LINESTRING), to a network?

I need to connect bus stops (points) to a network layer (OSM data). These bus stops do not lie directly on the lines (see screenshot) nor should their location be moved. I use PostGIS, pgrouting and ...
117 views

### PostGIS table to network analysis

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 ...
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### Split lines at intersections in PostGIS (must be simple but…)

I'm usually closer to my answer than now, but I've looked at all the answers here and couldn't adapt one to work on my data and I'm stuck. I have oriented polylines (Montreal's train network) and ...
76 views

### Suggest an algorithm to measure how a node is connected to road network

I try to measure how well a node is connected to the rest of the network. If a city has a distant suburb connected with one sole road, it's connectedness is, say 1. If it's connected by 2 roads, it's ...
94 views

### Traversing all possible road routes

I have created a topology from OSM data and would like to simulate a car driving every possible route along the map. The purpose is to "survey" the osm data as if in a car. My ultimate objective is to ...
104 views

### SQL procedure(s) to convert GPS traces to an ordered set of junctions in a network

I have three datasets that I have loaded into a geodatabase (spatialite or PostGIS): A set of GPS points collected from individual trips through urban areas. Points have a unique point id, a group ...
780 views

### Howto setup and use a remote GIS workstation (QGIS,GRASS,PostGIS)?

I'm using QGIS (and sometimes GRASS and PostGIS) on my 2009 MacBookPro for my thesis project. I was wondering (during an endless batch generalizing in QGIS) if I can set up a server so I can work from ...
285 views

### How to create routable network by pgrouting with assign_vertex_id?

I'm trying to create the routable network as per http://underdark.wordpress.com/2011/02/07/a-beginners-guide-to-pgrouting/and use assign_vertex_id. Do I still need to create the node table? How would ...
402 views

### Creating routable network table in PostGIS

I am trying to create the routable network table, as per http://underdark.wordpress.com/2011/02/07/a-beginners-guide-to-pgrouting/. Everytime I do it in PostGIS extension, QGIS crashes. The area is no ...
186 views

### PostGIS Implementation of Brabyn and Skelly Road Network Travel Time Model

Is there a PostGIS implementation of the Brabyn and Skelly road network travel time model for the New Zealand road network? This model is outlined in: Brabyn L, Skelly C. Modeling population access ...
414 views

### calculate slope for a road network

I am working on a road network for routing operations using postgis and QGIS. I am new to both of these tools and need to calculate the slope for each edge (by retrieving the Z value for the start ...
691 views

### Create closest point on multilinestring to use in shortest_path()

I am working a routing based application where I need to create a route between two points of interest. The problem which I am facing occurs after calculating network topology using ...
974 views

### How to simplify a routable network?

I have a network graph that I need to simplify in the sense of reducing the number of edges. The idea would be to merge nodes that are located close together and remove the connecting short edges. ...
689 views

### PgRouting - How to clip links when reaching max costs?

I have a polyline shapefile representing a road network and a second shapefile containing points. I would like to use PostGIS (presumably PgRouting) to identify sub-networks or service areas radiating ...