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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52 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 ...
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0answers
76 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 ...
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136 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 ...
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1answer
150 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
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2answers
230 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
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3answers
128 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
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1answer
206 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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30 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 ...
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1answer
151 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. ...
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1answer
165 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 ...
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2answers
97 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 ...
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1answer
658 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 ...
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60 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 ...
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0answers
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 ...
3
votes
1answer
238 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 ...
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0answers
77 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
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1answer
164 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 ...
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0answers
185 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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0answers
36 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
79 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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4answers
141 views

UK road network dataset

Can anybody guide me to a website or a source to download the Geographical UK road network data set. The data set should include the road distances, since I want to apply shortest path search ...
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0answers
125 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
80 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 ...
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1answer
595 views

How to assign node IDs to links in a network?

I have two shapefile layers in ArcGIS for Desktop 10. I have one line layer and node layer. My node layer(shp) has a "code_1" field and line layer has a "code_node" field. The intersection point ...
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0answers
25 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
61 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
39 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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1answer
650 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
193 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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28 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
76 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 ...
7
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1answer
309 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 ...
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3answers
208 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 ...
3
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2answers
217 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. ...
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1answer
149 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
77 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
786 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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0answers
43 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
votes
0answers
94 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 ...
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0answers
118 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 ...
5
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3answers
777 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 ...
6
votes
3answers
446 views

How to create an OD road distance matrix in QGIS?

I'm looking for the steps required to produce an origin-destination (OD) cost matrix. What I'm looking for is a matrix of road distances. The distance matrix tool only produces euclidian distances. ...
1
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1answer
59 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
282 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
102 views

Find directly joined neighbour points using a different line layer in QGIS

I have two layers of data: A set of points showing every significant point on the UK rail network (Network Rail Stanoxes). These are a mixture of stations, junctions, timing points and signals. An ...
2
votes
1answer
54 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
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0answers
433 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 ...
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2answers
120 views

SpatiaLite: Creating to, from nodes from a normal road layer (LINE)

Following this tutorial but using my own data. How do I create the from_node and to_node columns? I am using Spatialite and Sqlite3. I'd prefer to not use a gui as I'm working remotely via ssh on a ...
3
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2answers
557 views

Map walking distance/time from transit stops

I'm working in QGIS and would like to show how far from a bus stop a pedestrian could walk along the street network in any direction for a specified set of walking times (5,10,20 mins etc). I have my ...
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0answers
51 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 ...