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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6
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0answers
156 views

Can GRASS compute the line graph representation of an input graph?

I'm interested in computing a line graph for an input graph, preferably in GRASS since I'll be using other GRASS network analysis tools afterwards. I couldn't find any reference to line graphs in the ...
5
votes
0answers
770 views

How to use Route Task in Network analysis tools

I am using esri network analysis tool and I just want to draw the path between two clicked point on the map (by using route task) I use the example code block in the following link ...
4
votes
0answers
21 views

“Merging” 2 layers of LineString with splits at intersections

I would like to "merge" 2 networks of lines and these lines need to be split when they intersect. With pictures it should be clearer : What to do: if a black line intersects a red line, they ...
3
votes
0answers
27 views

Calculating a specific distance from points along a network - GRASS

I'm currently using the v.net.iso function in GRASS (no access to network analyst in ArcMap). Does anybody know of a way to export the result to shapefile so that you have an individual line ...
3
votes
0answers
55 views

How are costs returned by the pyQGIS implementation of Dijkstra calculated?

How are the costs returned by pyQGIS implementation of Dijkstra (QgsGraphAnalyzer.dijkstra) calculated? As far as I know, these costs correspond to the distance from the starting node to each of the ...
3
votes
0answers
85 views

Steiner tree problem: Optimal routes for Fibre planning on road network

I am trying to solve a large optimization problem where I have a set of nodes on a road network that need to be connected using fibre using the shortest possible amount of fibre. The problem is a ...
3
votes
0answers
157 views

Is it possible to create Isochrones in QGIS GUI?

I'm new to QGIS and have tried to create isochrones around points for quite some time. Is there any option to create isochrones on the GUI in QGIS? I know how to create them using pgAdmin (using eg ...
3
votes
0answers
82 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 ...
3
votes
0answers
165 views

Three Dimensional Routing Input Location Errors and Questions, ArcGIS10

I am having a bit of a problem with my three dimensional route solving. I am creating an interior building network, and ideally would be routing from room to room. I created a line feature class, with ...
2
votes
0answers
10 views

Can I use Mapbox to create a web form that finds parks near a location?

I have run a network analysis in ArcGIS and have all of the trimmed polygons along roads within a half a mile of a park. I need to find a way to create a web form that takes in an address and spits ...
2
votes
0answers
35 views

How to calculate shortest path from points in one layer to points in another layer via roads, in QGIS

I'm a new user of QGIS (and have experience using ArcGIS but zero programming skills) and I'm looking for a way to calculate the shortest path from addresses to subway stations via a network of roads. ...
2
votes
0answers
89 views

Finding number of left and right turns for each shortest route

I have a network dataset for a city. I have, lets say, 200 trips that are made in that city. I constructed the shortest route for the every pair of the trips, and also the actual route travelled by ...
2
votes
0answers
117 views

How to build a GRASS network with node IDs from the line dataset?

I have a dataset of street network links (line geometries). Each network link has a link id, start node id, and end node id attribute. I want to use this network in GRASS, so after importing the ...
2
votes
0answers
71 views

inputing road network as nodes and arcs in java

I want to input a road network as nodes and arcs. Some of the nodes are intersections, others serve to describe the shape of the road. Road network should be modeled as an embedded graph consisting of ...
2
votes
0answers
58 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 ...
2
votes
0answers
27 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. ...
2
votes
0answers
26 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 ...
2
votes
0answers
31 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. ...
2
votes
0answers
570 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 ...
2
votes
0answers
168 views

Plot the Shortest Paths in a Grid without any clash at a point of time

The efficient algorithm needs to be done and proved for the best solution for the given problem: User inputs: (#) Size of the NxN Grid. (N); (#) No. of Paths: Z; (#) Source and Destination ...
1
vote
0answers
22 views

Geoserver VM with NAS, Should I store entire VHD on the NAS or just map the data directory? Or just go with internal SSDs w/ weekly backups?

Our humble geoserver instance needs to be able to host GEOTIFF image pyramids ranging in size from a few gigs to a few TBs. A NAS appliance with raid 10 seems smart from a maintenance/expandability ...
1
vote
0answers
29 views

Adding multiple values restriction field for service area analysis using ArcGIS Network Analyst?

I have a network dataset created and I am trying to run a service area analysis for pedestrians/cyclists movements. The network is comprehensive of pedestrian paths, cycle lanes and roads as well, so ...
1
vote
0answers
24 views

Network analysis library - example from PYQGIS developer cookbook does not work

I am using QGIS 2.6. I'd like to be able to calculate the driving distance between any two geocoded locations (can't use the shortest path roads plugin because it appears to be interactive and I need ...
1
vote
0answers
40 views

How to modify the “Network Analysis Library” in QGIS?

I want to modify the network analysis library because th graph builder does something I don't want. When there is an intersection between to lines, it creates a node in it. I want to avoid this ...
1
vote
0answers
50 views

Matching vertices in igraph (R)

This is my first question so apologies if it's poorly explained... I'm currently using a combination of ArcMap 10.2 and igraph in R to analyse a network with associated data. I have an igraph ...
1
vote
0answers
75 views

Computational Geometry Problem

I have following datasets- Road network (line) Waterbodies data (polygon) School locations (point) Suberb boundaries (polygon) Property boundary -buildings (polygon) What i want- Generation of ...
1
vote
0answers
166 views

Removing pseudo-nodes using QGIS Sextante plugin?

I have a road network (vector) that i'm interested in carrying out some space syntax analysis on. Predictably my GIS data is in a pretty terrible state. For example, there are a bunch of roads on the ...
1
vote
0answers
98 views

What is the reason for the very poor performance of ESRI's file geodatabases on network drives?

I am asking this question because I am at a loss and dont have a good enough understanding of all the underlying operations going on 'under the hood' of Windows/Arcgis. What is the root cause of ...
1
vote
0answers
33 views

An algorithm that could find a random cycle in a graph

I am looking for an algorithm that could find a random cycle in a graph from a node while that cycle is traversing around another nodes (area). For example, from the green star on the left of the ...
1
vote
0answers
158 views

Representation of road networks at junctions when line width is varying with attribute

I have a road network and for every road segment the average number of daily traffic. I need to draw a map where the line width for each road segment is proportional to the daily traffic. I can do ...
1
vote
0answers
64 views

GRASS GIS: Network analysis doesn't work correctly

I got a problem with the Network Analysis function v.net.iso in GRASS. I tried it so many times but the function doesn't work correctly. I tried to calculate isolines via the function v.net.iso, based ...
1
vote
0answers
17 views

Route From Network Analyst Not Fully Displayed

I am working on a project for finding the optimized route solid waste pickup within a defined neighborhood. These are my setting for route properties. The curb approach must always be on the right ...
1
vote
0answers
64 views

how to use line feature as stops input in network analyst?

I'm trying to build a certain route with network analyst on a Network Dataset. As an input to create the route I want to use line features. I am trying to do this with network analyst in ArcGIS 10.0 ...
1
vote
0answers
68 views

pgRouting with TomTom multiNet

I would like to use TomTom multiNet data with pgRouting to create drive time/distance polygons. I have gone through the documentation regarding network topology creation, but am still confused to ...
1
vote
0answers
200 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 ...
1
vote
0answers
63 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 ...
1
vote
0answers
76 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 ...
1
vote
0answers
121 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 ...
1
vote
0answers
35 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
vote
0answers
136 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 ...
1
vote
0answers
242 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 ...
1
vote
0answers
173 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 ...
1
vote
0answers
289 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, ...
1
vote
0answers
136 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 ...
1
vote
0answers
68 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 ...
1
vote
0answers
396 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 ...
1
vote
0answers
224 views

Map Matching? (Finding Nearest Roads…)

I am making Pedestrian Navigation System for my school I created node and arc and digitized buildings with ArcGIS. Then, exported KML to use Javascript Dijkstra's Algorithm to find route. So far, so ...
1
vote
0answers
88 views

Stopping the automatic snap to locator in Arcgis 10.0 reverse geocode

I built a network application using arcgis 10.0 sdk for wpf. The application uses a locator of highway milestones to reverse geocode (and identify) the "flag" the user clicked on the map. My Problem ...
0
votes
0answers
11 views

Create matrix measuring distance from each point to every other point along polylines

I'm working on a project involving ancient trade routes. I have two datasets: 1) -Nodes (around 1000): Every node has a nodeID, lon, and lat 2) -Arcs (several hundred): contains a record for each ...
0
votes
0answers
21 views

Live GPS tracking with both ping script

That's a professional context : During a travel between two train station, I would like to use the live tracking and analyse the network performance (access by Wifi & 3G/4G ). I would like to ...