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.

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31 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 ...
1
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0answers
90 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 ...
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0answers
198 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 ...
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1answer
210 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 ...
4
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2answers
646 views

Does pgRouting support turn-by-turn routing? [duplicate]

I have route list as result of pgRouting with street names. How to get messages "Turn left", "Go along" etc ... Can pgRouting do this or I need some other source and which?
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0answers
46 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 ...
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1answer
84 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 ...
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0answers
140 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 ...
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1answer
99 views

Analysing a network distance to two or more points using GRASS or QGIS

I am doing a piece of analysis work looking at distances along a network in GRASS. Most of the analysis involves finding which parts of the network are within 600m of a series of points. GRASS does ...
2
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1answer
2k views

How to find the watershed area for each point in the river network using DEM?

Update#1: Thanks, Micha, I have followed your instruction and successfully use the modules in GRASS. I use r.watershed to get the basin raster and the drainage line: and I use r.water.outlet to get ...
2
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1answer
798 views

Read and Export OSM Road Data as a Network of Road Segments [Adjacency Matrices]

I wish to extract from an OSM file a road network, and export it as an array (adjacency matrix) where the nodes are the road intersections and the edges represent the road segments. I don't want to ...
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0answers
28 views

Why outside border of a service area is always not reasonable?

In ARCGIS 10.1 network analysis, why results of service area are different if number of break points is changed? For example, the grid is 300m*300m, I try to produce service area around a node. ...
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2answers
63 views

How do I create blocks from a road network?

I have a road network and for every enclosed area within the network I want to create a polygon that represents that area. How does one do this?
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1answer
41 views

How to compute drive access to a station based on vehicle origin points? [closed]

I have a shapefile that contains station locations and another shapefile that is the geocoded origins of those who drove to the station. I would like to make a buffer around the station that shows the ...
2
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3answers
368 views

How to route railcars along railroads?

I'm very new to the world of GIS, but I'm learning a great deal from this site, as well as others. I fell like this should be 'easy' but I need to be pointed in the right direction. I'm trying to ...
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0answers
219 views

Drawing a road network: offsetting overlapping lines (directed graph)

Say I have a road network defined by a table, indicating, for each arc, its ID, and its head and tail node. In other words, my network is defined as a directed graph. For example, we have two points, ...
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0answers
29 views

How to turn this into a routable network that works with pgRouting? [duplicate]

I'm only asking again since I didn't get any answer and I'm still stuck here... I updated my last question with more info, but it wasn't answered. When I draw a line with snapping enabled and try to ...
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1answer
82 views

How to make pgRouting understand bridges and tunnels?

I have I highway that runs on a bridge over a couple of blocks in a city. How do I get pgRouting to understand that cars can't move from the small blocks on the ground up to the highway on the bridge ...
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3answers
218 views

How to convert Midpoint of Polyline into Point Feature using ArcPy?

I am trying to write a python script to determine flow direction on a water pipe network. I've used this script to find the mid point along each polyline, now i need to convert this data into a point ...
7
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1answer
330 views

Do ModelBuilder or Geoprocessing tasks run slower if screen locked?

Is it true if you are running ModelBuilder or a geoprocessing task on a large raster\vector dataset then locking the computer would that cause the ModelBuilder or any geoprocessing to run slower? Is ...
3
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2answers
255 views

Create network from shapefile without ArcGIS?

I want to perform shortest-path analysis on a network whose edges represent real-world roads and whose nodes are buildings or other locations. I have the shapefile for the area I'm interested in. ...
6
votes
1answer
569 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 ...
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1answer
171 views

Creating a point buffer along a road network [duplicate]

I have a road network and have added points indicating fire hall locations. How would i go about creating buffers on those points following the road line. The result am i looking for would create a ...
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1answer
90 views

Infrastructure networks in GIS modelling

I am currently working on a GIS-based project which aims to model the interdependency of existing infrastructure networks, e.g. transport, oil, pipeline networks, etc. The network interdependency ...
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1answer
866 views

How to build a Spatialite road network from OSM data

I'm looking for algorithm which could help me with building my own road network (for routing) from OSM data. I chose Spatialite DB for this, but here I have only one problem: Spatialite provides ...
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2answers
244 views

how to build a routeable network for pgRouting with srid 3785

I'm following the pgrouting-workshop http://workshop.pgrouting.org/chapters/topology.html and It works, but in my project I'm working with the mercator projection(srid 3785) and there is not a routed ...
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0answers
46 views

Time attribute problems with Network Analyst [closed]

My network dataset is in a geographic coordinate system, and when I project into UTM to calculate Miles for a length field to use with my Speed Limits to create a time attribute it does not seem to ...
3
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0answers
106 views

District heating expansion design with ArcGIS [closed]

I am quite new at GIS but I have some experience of the basic concepts involved in a workflow of them. What I currently want to do is to calculate the cost of expanding an existing district heating ...
5
votes
3answers
897 views

Tracing up a stream network & tabulating attributes of polygons it passes through

I have an ArcGIS question that is either very easy or impossible (my favorite kind). I am somewhat inexperienced when it comes to dealing with network analysis, so maybe I'm missing something major ...
14
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6answers
1k views

What is the best method of visualizing a network on a map?

I have several hundred geo-referenced data points, and the relationships from that point, to other points. I'm trying to figure out the best way of visualizing this on an interactive map (possibly ...
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0answers
128 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 ...
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0answers
129 views

how to set in arcgis network analysis that use every road segment max m times? [closed]

excuse me if my english ins't good. I have one incident and 120 facility. i wanna set criteria in Arcgis network analysis that if any road segment used for example m times, for other route doesn't use ...
0
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1answer
84 views

Adding additional nodes to network in Grass GIS

I have created a network in Grass GIS (using v.net, nodes option). I then want to "disrupt" the network (i.e., create some road blockages) and add in nodes to the new line ends where road blockages ...
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1answer
67 views

how to extract network of city routes from city blocks shape file?

I have a shapefile which contains urban blocks. So, I am going to extract network shapefile of city routes and calculate total length of network arcs. I am using arcgis 10 for this work. Is there any ...
7
votes
4answers
301 views

Automatic matching of two street networks

I'm faced with the problem of matching two street networks. I have these two differently sourced networks. The links in each network can be segmented, i.e. there is not necessarily a single whole link ...
1
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1answer
838 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 ...
2
votes
1answer
98 views

Why does IDatasetContainer2.CreateDataset fail with ArcObjects at ArcGIS 10.1?

I have a small application used to check and generate network, created with the help of the following tutorial: http://help.arcgis.com/en/sdk/10.0/a...00000w7000000/ It worked just fine with ArcGIS ...
1
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1answer
173 views

ArcView: Trim polyline, that is shorter than specific dangle length (alternative to tool: Trim Line)?

I am looking for a way to trim dangles from a polyline shape, that are shorter than a specific length like the Trim Line Tool for ArcEditor and ArcInfo, but with ArcView-License. I already discover, ...
0
votes
2answers
306 views

Geoportal to harvest services hosted by Geoserver

I am trying to set up Geoportal to harvest services hosted by Geoserver. I tried follow this instructions: Open your Geoportal Server. Go to the Administration tab Choose the 'Add' option Choose ...
2
votes
1answer
59 views

Conceptually, what's the ideal way to develop detour maps for a large number of nodes

I have a road layer of roughly 30,000 links. On these links, I have a total of 15,000 nodes that are sorted in a point layer. I'm trying to build a detour distance and routing around each asset in ...
2
votes
0answers
481 views

How to specify cost attributes for network analysis in QGIS using the GRASS plugin?

I have a road dataset with information about the length, speed and drivetime for each segment. I use QGIS 1.9 with the GRASS plugin to do different types of network analysis, but how do I set up the ...
31
votes
8answers
3k views

Representation of network flows

This is a sample transportation network flow I've done a year ago based on 26 zones. For a project I'm working on now, I need to represent the flows over 1,000 zones with directionality. Any ...
3
votes
3answers
1k views

Design fiberoptic network in QGIS?

I'm a GIS newbie trying to design a fiberoptic network in QGIS. What I'd ideally need is to draw lines on top of a map or orthophoto, assign a name/id to each line and a type. Get a list of all the ...
1
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0answers
56 views

Deleting network features in python script doesn't create net junctions

I have a script that makes a copy of a network dataset for a 3rd party app to use. One of the junction feature classes causes problems with the app. The ideal solution would be to remove it from the ...
2
votes
4answers
253 views

Render a map showing lots of individual traces/routes simultaneously

Google's "My places" is great for showing lots of traces (in my case, paths representing bike rides I've done). But it only shows 20 or so per page. I'd really like a map (a statically rendered .png ...
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0answers
276 views

Calculating walking routes along a network(ArcGIS)

I've created a network consisting of footpaths, dirt tracks and junctions. I would like to calculate a route using network analysis by giving ArcMap the time and walking speed that the route should ...
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2answers
92 views

How to develop a fastest road website?

I need to develop a website to find the fastest road between two points (just like google map) What kind of technologies I need to use? What are the components of this project (database, website, ...
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1answer
110 views

Clipping without cutting features

I want to create a multimodal network dataset for the city of Montreal. I have roads and transit lines features for Quebec province (where Montreal is). Because I need the features limited to Montreal ...
20
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7answers
2k views

Alternatives to Network Analyst

I'm not sure how reasonable this question even is, but it leaves me no less curious after a bit of searching. If I am looking to build a network based on road features and attributes, is Network ...
7
votes
2answers
746 views

Conflating Two Network Datasets in ArcGIS

I am looking to merge two network datasets in ArcGIS 10.0. I have an ArcInfo license and have trawled this forum but am looking for some clarification. I want to merge two road networks but only make ...