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

1
vote
0answers
4 views

Create network graph from PostGIS boundaries, or KML file?

I am using Postgres 9.5 and PostGIS. I have a table with a geometry field. This table has about 200 rows, in each of which the geometry field contains a Polygon. I would now like to derive an ...
1
vote
3answers
161 views

Creating network datasets from OSM data in QGIS?

I am having a difficulty to use network analysis in ArcGIS because of unavailable network datasets. So, I googled it and realized that it is possible by using OpenStreetMap. However I don't know how ...
0
votes
0answers
14 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 ...
2
votes
0answers
12 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 ...
14
votes
2answers
5k views
+200

How to calculate Network Service Areas in QGIS?

Is there any way in QGIS to apply service area buffers e.g if I have a point on a map I wish to show the service coverage of 1 mile, 2 mile, 3 mile, breaks using the road network?
2
votes
0answers
30 views

Buffer for network roads in QGIS [duplicate]

How can I create "buffers" or vector from values ​​from a layer of points, where the "buffers" are "tied" to the streets? Example: A bus station, I would like to create vectors within 100 m range ...
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 ...
5
votes
3answers
612 views

Network distance computations using GRASS

I'm an ArcGIS user who's interested in learning to use GRASS. Can anyone point out resources that will help me in learning how to obtain network distances between (1) residential locations (points) ...
5
votes
1answer
642 views

Road Topology Problem solution for junction

I am working with a Road Network. I have digitized the lines with AutoCAD Map 3D. Then Imported it to ArcMap. After entering all kind of database I have created Routing Dataset. But unfortunately its ...
3
votes
1answer
187 views

QGIS 2.6 simplify a road network to obtain the intersections

In QGIS 2.6.1 in Ubuntu, I want to measure the density of block in this city (FYI my final aim is to measure the TOD level). I have the road network from French national IGN dataset BDTopo. I have ...
25
votes
11answers
7k views

Alternatives to pgRouting

I was wondering if there are any alternatives to pgRouting tools. Thinking about it for a bit, I think the only alternative is to use R or RPY to do the analysis. Basically I'm trying to solve ...
7
votes
2answers
671 views

Is there an open source tool to planarize graphs?

I read about the planarize function in ArcGIS, which seem to do exactly what I want. Is there a similar feature in QGIS or another free tool? I have a shapefile with various shapes intersecting each ...
2
votes
1answer
200 views

How to use GRASS v.kernel to calculate point densities along a network?

In a road network, I need to select the segments where a minimum of 5 dots occur (1 dot = 1 address) over a distance of 100 m (the image attached illustrates my question). I'm trying to use GRASS ...
1
vote
1answer
17 views

Any standards for urban rainwater drainage network?

I am starting to work on a project related to urban drainage networks. Are there any standards out there to represent this kind of network? Relevant attributes would be things like pipe section, pipe ...
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 ...
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 ...
1
vote
0answers
23 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 ...
8
votes
2answers
1k views

Selecting only canals that are connected to reservoirs?

I have a polygon layer of water reservoirs and a polyline layer of canals. In my data, some canals are originating from reservoirs, and leading to other canals. On the other hand there are some ...
8
votes
3answers
1k 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. ...
4
votes
2answers
151 views

Road segments reconstruction from GPS trajectories

We have a 10,000 base of vehicle mounted moving devices which report their GPS position on a time based schedule. All that data is currently being stored in our database for several business related ...
2
votes
3answers
213 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 ...
3
votes
1answer
31 views

Get upstream sections of a network

Is there any extension to get all upstream sections of a polyline shapefile which represent an hydrographic network in QGIS? It could work like this: you choose a specific branch and a direction ...
1
vote
1answer
29 views

Navigating a road network and avoiding u-turns

I've implemented a node-based A* search of a road network graph. I would like to penalize u-turns a places where bi-directional streets join together again, which I identify successfully via a match ...
2
votes
1answer
54 views

Reproducing GRASS GIS network analysis tutorial in QGIS Field Calculator

Im looking to reproduce the assigning of road speeds as denoted in a GRASS GIS tutorial (v.net.alloc tutorial), where the road speed is assigned by road type (i.e. 'interstate' = 75 mph etc.) to then ...
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 ...
0
votes
0answers
16 views

Nested Set Model for Spatial Data?

How can I create a nested set model for a spatial line dataset? The nested set model is a technique for respresenting hirarchies of a tree (see https://en.wikipedia.org/wiki/Nested_set_model). If ...
1
vote
1answer
65 views

ArcGIS Online Network Service

Where does ArcGIS Online Network Service source came from? Is there any source reference I can refer to? I tried to search on Google but I could not find anything.
0
votes
0answers
34 views

How to find NetworkAnalysis extension with ArcObjects?

I'm using ArcGIS 10.0 My code: IAoInitialize init = new AoInitializeClass(); var a= ...
53
votes
10answers
19k views

Creating drive time polygons using Open Source tools?

Is anyone using open source tools and/or data to generate drive time polygons that radiate out from a given location? For example, I have used ESRI products like Network Analyst and Business Analyst ...
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. ...
0
votes
0answers
18 views

How do I add a fixed cost for switching modes in network analyst? [duplicate]

I am constructing a multi-modal transportation network using Network Analysis in ArcGIS. I have data on roads, railway, and rivers. My goal is to calculate an Origin-Destination matrix of the cost to ...
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 ...
0
votes
1answer
49 views

Can you create a square OD Cost Matrix with Network Analyst?

I have a feature dataset and want to find the cost of travel between each pair of features. Because I'm looking for road (not Euclidean) distances, I was told that the OD Cost Matrix solver in Network ...
2
votes
1answer
45 views

Network generation algorithm

I am trying to solve a network generation problem, and I'd be happy about inputs. First of all, my problem description: I have a list of connections between locations with respective distances. For ...
3
votes
1answer
114 views

Calculating shortest paths from all points in one layer to any points in another via road layer in QGIS?

I'm trying to calculate the shortest paths from all the points in a layer representing population settlements (the green points) to any of the points in another layer representing the hospitals ...
0
votes
0answers
39 views

Water main Flushing

I am trying to make a basic network on which I can derive some watermain flushing routes (similar to the software InfoWater UDF). Watermain flushing depends on closing specific valves to direct water ...
0
votes
1answer
26 views

Does ArcGIS Online include High Speed Rail in its network analysis?

I'd like to run an OD Matrix using network analyst in Europe and Asia to study high speed rail. Does ArcGIS online include HSR (such as the AVE in Spain or the TGV in France) in its analysis?
4
votes
2answers
264 views

Can ArcHydro tools be used on a network in an SDE enterprise geodatabase?

Most of the documentation for ArcHydro tools discusses their use on data in ESRI's personal and file geodatabases. Is it possible to use ArcHydro tools to set network flow direction on a networked ...
1
vote
3answers
90 views

Filtering polyline features by direction using ArcGIS 10.2 (or ArcPy)

I have a polyline shapefile depicting a real road network. In many parts it has two 100 % overlapping segments in opposite directions, representing the two driving directions (In picture: red ...
1
vote
1answer
75 views

Update values from layer one to layer two where there is no identical ID but identical geometry

I have one huge problem and that is to get the value from one layer into another. It is a network with over a million links and I need to update a table from a layer of + 100 000 links. I am using ...
6
votes
2answers
3k views

Segment road network line shapefile into new equal length segments line shapefile?

I would like to subdivide a road network for an entire state into segments of equal length. So, Highway X would be divided into 0.5 mile segments, with a record for each segment, and Highway Y would ...
2
votes
0answers
87 views

Error when stop editing a feature in ArcPy [closed]

I want to make changes in a feature attribute table that is an edge source of a Network dataset. In the next step, I need to rebuild the Network to make the changes take efect. The problem is that, ...
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 ...
32
votes
8answers
5k 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
1answer
31 views

Distinguishing Road Network according to the ward within a municipality ArcGIS

I have a polygon layer of a municipality containing 14 wards as shown in figure i. I also have a polyline layer of road network irrespective of the ward. The road network have following attributes ...
2
votes
1answer
69 views

pgrouting calculate length of shortest travel time route

I currently use the pgr_kdijkstraCost() function to calculate the travel times of a few origins and destinations. But I would also like to return the distance length of these trips. Is this possible? ...
2
votes
1answer
60 views

Adding elevation data to a network dataset

I am trying to add elevation data to my road network to more accurately calculate walking distance to and from schools. I have figured out how to do the network with out elevation, but for the life of ...
0
votes
0answers
24 views

'D8 contributing area method' - TauDEM with QGIS

I'm using the TauDEM on Qgis to extract drainage area network from DEM. I could do it easily using the threshold method of TauDEM. Now I would like to do it using a shapefile of the inlets of the ...
1
vote
2answers
73 views

Distance between two points in a line feature

I have two layers, one with lines and the other with points. Layer one has all the points (A to J) as shown below and layer two has all the lines connecting these points. Is there an automated way (in ...
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 ...