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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7 views

How to determe upper most point in stream based on gradients? [on hold]

I am trying something I have never tried in my GIS career 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 ...
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16 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 ...
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1answer
79 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 ...
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2answers
20 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 ...
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1answer
211 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 - ...
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54 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 ...
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1answer
41 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 ...
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1answer
23 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 ...
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1answer
112 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 ...
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2answers
32 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 ...
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42 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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50 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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56 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
66 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 ...
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2answers
123 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 ...
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3answers
86 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
102 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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27 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
60 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
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1answer
79 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
73 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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0answers
429 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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28 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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28 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
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1answer
127 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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57 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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1answer
83 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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31 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 ...
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10 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 ...
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106 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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38 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 ...
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19 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
72 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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3answers
66 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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90 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
53 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
201 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
20 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
55 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
37 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 ...
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1answer
305 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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136 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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26 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
57 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
218 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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3answers
165 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
152 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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71 views

Network Analysis-shortest combined distance to one point

First let me confess I have little experience doing network analysis so I assume I know nothing (in essence approach me like my girlfriend does). Anyway, I am attempting to solve what I believe to be ...
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1answer
98 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
61 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 ...