Tagged Questions

An interconnected set of points and lines that represent possible routes from one location to another, OR in computing, a group of computers connected in order to share software, data, and peripheral devices, as in a local or wide area network.

learn more… | top users | synonyms

2
votes
0answers
12 views

QGIS GRASS shell commands not working in Yosemite

First time asking a question here. Running GRASS 2.4.3 within QGIS 2.4.0 on Mac OS 10.10 Yosemite. I'm trying to run v.net.iso within the GRASS shell, but the following error is returned every time: ...
1
vote
0answers
16 views

How to import and display a road network in XML to ArcGis?

I am trying to convert xml data to shapefile features using ArcGis 10.1. Im using the open source SUMO traffic simulation software. Part of the model process is to convert OpenStreetMap road network ...
1
vote
0answers
22 views

Asset point IDs, pipeline and flow direction

I have a data set of a sewage pipe network and point data (assets). I would like to: first calculate the flow direction of pipes (polyline feature) assign IDs to the pipelines using asset IDs ...
0
votes
1answer
19 views

pgRouting can't find route at intersection

I have a simple path that is defined by two polylines: The first line goes from point 1 to point 2, and the second from 3 to 4. After running the pgr_createTopology script the source and target's ...
3
votes
2answers
55 views

Identify all continuous networks in a dataset

I have a set of pedestrian streets for a city. I would like to assign all of the streets that can be reached to one another along a continuous network to a unique group. I am wondering if there’s an ...
2
votes
1answer
19 views

Harvesting pixels using GRASS GIS

having a binary raster map of pixels of interest, a road network, and a target point, my goal is to get a raster map with network pixels having as value the number of pixels of interest they allow to ...
2
votes
0answers
18 views

Path on network returning wrong results

I have created a shapefile of polylines that represent a path with multiple intersections. Then I have used the networkx python library to create a network. At the first the results were satisfactory. ...
1
vote
1answer
31 views

How to create a routable network with PGRouting

I have two sets of data Table A: Stations - contains postal code (which I can convert to lat/long), name and code. Table B: Connections - contains a possible list of connections including source, ...
3
votes
3answers
61 views

Hierarchy not working in network analyst

I have created a simple network to test hierarchy. But apparently I am missing something. I have created an attribute for my roads called hierarchy and given it values of 1 to 3. The network is set to ...
1
vote
0answers
29 views

How does Address Locator pick one of two alternative points in ArcGIS for Desktop?

I have geo coded the main entrance of buildings on my map and some buildings have more than one entrance. How does address locator pick one of them? To me it seems it is just randomly picking one of ...
-3
votes
1answer
182 views

How to extract drainage line network from GRASS GIS and QGIS [closed]

Giving DEM as input is there any way to get drainage network? I am newbie to GRASS and QGIS ,provide any working examples in GRASS GIS and QGIS with procedure.
0
votes
2answers
69 views

Shapefile to Network xml

I have a shapefile representing the US freight highway network available from Oak Ridge National Lab. I'm trying to prepare this as a .xml network for processing with MATSim. The output structure is ...
2
votes
0answers
13 views

Route Analyst acts odd at using custom impedance

I need to do a route analysis with a custom made impedance, which is impedance based on the surface type. Here is the problem: while the route Analysis acts perfectly fine with the default cost ...
1
vote
1answer
32 views

Unable to access GeoServer from another computer in the same domain

I installed GeoServer 2.5.2, GeoNetwork 2.10.3 and Tomcat 7 on my Windows 7 computer {MyComputer} in our company's network. Now I would like to access GeoServer, GeoNetwork and Tomcat from other ...
2
votes
2answers
58 views

How to batch run an FME workspace on a feature basis?

Not sure about the title of my question... My point is to run an entire workspace for each feature contained in a reader. In python this would look like: for s in bus_stops: run_workspace(s) ...
4
votes
1answer
55 views

Workflow for adding Pipe Systems to QGIS

I want to layout a concept design for a sewer main in QGIS. I have a variety of background information: Aerial Imagery Services from various sources DEM from LIDAR Lot Boundaries I want to ...
2
votes
1answer
88 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 ...
1
vote
0answers
51 views

Determining uppermost point in stream based on gradients?

I am trying something new and was hoping someone out there may have done this same process or something similar or may have a best approach. For this particular project I am working with ArcMap ...
0
votes
1answer
80 views

How to perform an attribute-weighted sum of multiple polyline features from a single vector layer?

I have a shapefile of ~8000 polyline vector features representing traffic journeys on road routes. Each has an attribute representing volume of traffic for that journey. The routes are all generated ...
4
votes
1answer
127 views

What are the existing datasets of world maritime routes?

I have a list of cargo ports of all over the world and need to show some port-to-port trips on a map, and also to compute lengths of these trips. For that, I need a dataset of actual maritime routes ...
0
votes
2answers
27 views

Adjacency matrix in GRASS

I have a line shapefile that I use as network. I connect a set of point to it using "v.net operation connect" command. . My questions are: (i) how can I get the list of neighbors for each ...
9
votes
1answer
577 views

How can I improve the speed at which QGIS 2.4 handles network data? (Seems much slower than 2.2 - even with small datasets)

I recently downloaded and installed QGIS 2.4 Chugiak on a Windows 7 64-bit machine with a quad core processor and 8GB RAM. I'm having a few problems using datasets of all sizes from a network drive - ...
3
votes
0answers
66 views

How to find the minimum number of inspection points?

I am working on a pipeline inspection project and there is a high liklihood that some inspection tool deployment/retrival station will need to be installed on the pipe network. the problem is ...
0
votes
1answer
46 views

What is the right methodology to assign costs to edges of a network?

I am producing a routing facility for cycling safety based on an OSM network. The edges of this network have costs and these are calculated from different criteria both related to intrinsic (as the ...
0
votes
1answer
35 views

Get attributes from intersecting lines to label generated intersection point

I have an urban road network (as a feature class), consisting of only polylines. I have to make a database of all the intersections between the streets. The problem is that as I generate those ...
2
votes
1answer
133 views

Route to cover entire network

I have a road network where I have to cover every road for visual inspection. I need to design a route map for this task. What tools are available to a QGIS user? How would you describe the workflow ...
0
votes
2answers
48 views

Overlapping lines, separate feature classes, get information out

I have a series of feature classes that represent trail systems with hiking times. They are straight lines between two known points. I generated these classes by interviewing various people on their ...
1
vote
0answers
47 views

Examples of evolving networks in GIS [closed]

I'm a master student working on networks analysis in general. A network is something that has nodes and there are links between the nodes. Nodes and links could have attributes. An evolving network is ...
1
vote
0answers
66 views

network based interpolation methods, which one could I use?

I need to interpolate traffic data consisting in raw number of vehicles passing across certain points, where counters are. It is evident I haven't a uniform distribution of points and values about ...
0
votes
0answers
84 views

Finding shortest cumulative route (i.e. best 'hub') between networked points

How do I find the shortest cumulative route (i.e. best 'hub') between networked points? I have a dataset where some but not all of the points in the network connect to each other, however it is ...
0
votes
1answer
94 views

Geoserver deploy over lan

I have set up geoserver on a mac mini running osx mavericks. i have my mac hooked up to my LAN and would like to start developing geographic web apps. I have a bunch of data sitting in my ...
4
votes
2answers
153 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 ...
2
votes
3answers
105 views

Creating a simulation of how people moving around a site

I am working on a project aiming to create a geographic simulation for how people interact around a site. Situation: There are x people in an enclosed area (such as a zoo). There are y locations to ...
4
votes
1answer
164 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 ...
0
votes
0answers
28 views

calculate distances between different components in a (cable-) network

I have to calculate all distances between every different components in a cable network (for example the distance between an amplifier and a modem) and have to show the results in a diagram (frequency ...
1
vote
1answer
88 views

How do you remove isolated roads from a bigger network?

I'm trying to perform an OD Cost Matrix calculation on a set of points using a road network from OpenStreetMap data. The network contains lots of roads that don't connect to the rest of the network. ...
3
votes
1answer
109 views

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 ...
1
vote
2answers
85 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 ...
2
votes
1answer
525 views

QGIS 2.2 problem, loading layer into road graph

I have the road graph plugin installed, but when I try to configure it with the Settings dialogue, no layer names appear in the Layers field. I have tried various shapefiles, but the Settings dialogue ...
0
votes
0answers
43 views

Why don't my service area polygons follow my network?

I have found a few similar questions, but no good answers, so here goes another Service area question: I'm working on creating a walking distance layer from Parks, and have a road network set up with ...
1
vote
0answers
29 views

What can I do in qgis to manage a WMS frequently unreachable?

In my project I have a layer linked to an external WMS server (provided by a local institution). The problem is that it is somewhat unreliable: it is down rather often. Is there something I can do to ...
3
votes
1answer
168 views

how to create a network from gps tracks?

I'm trying to build a network from several GPS-trakcs, to digitalize hiking routes on my land. I have several GPX-files from routes I've tracked with the gps. I managed to display them in Arcmap ...
1
vote
0answers
66 views

Network trace using attribute as a stop/barrier - ModelBuilder

I have two point datasets, one to be used as the flags(starting point) that i'll call dataset A and one as the barriers(stop point) that i'll call dataset B, in the trace(downstream) tool. In each of ...
2
votes
1answer
124 views

Alternative way to generate service area in ArcGIS - No Network Analyst License

I am working on a project currently that relates to creating service areas for points across California based on streets. I created a python script that can take a point and create a buffer around ...
0
votes
0answers
42 views

problems using GRASS v.net and v.net.allpairs

I am using GRASS 6.4.3, and I am trying to use it to do network analysis. I have a line shapefile and a point shapefile, and here is my code(I take v.net.allpairs as my reference): v.net tc_bf25 ...
0
votes
0answers
13 views

problems using v.net.allpairs

I am using GRASS 6.4.3, and I am trying v.net.allpairs to do network analysis. I have a line shapefile and a point shapefile, and after I use v.net.allpairs, I type the command d.vect network, and I ...
1
vote
0answers
138 views

how to add polylines(routes from public transport) on postgresql(pgrouting) with GUI

After searching a several long time... i decide to ask here for help, im currently using ubuntu 12.04(because of compatibility) with postgresql 9.1, postgis2, pgrouting2 and qgis2.2 i need ...
0
votes
0answers
45 views

Topology rules for a 3d network

I am currently writing a spec to which people may end up using to guide the digitization of a large 3d network (exterior pedestrian network + building interiors). In 2d network drawing, it seems to ...
0
votes
0answers
22 views

How to add a road to a network dataset

I have a street network file, and I want to add a section of road to it. I start editing on the road network dataset, snapping on, create a new feature line road segment from the edge of the old road ...
1
vote
1answer
74 views

How does the tolerance influence QgsGraphBuilder and tieing of points?

I am developing a script which uses OpenStreetMap data to calculate the distance (over the road network) between each building and the nearest hospital. To do this, I mainly follow the official ...