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

0
votes
0answers
4 views

How to solve “features were not reachable” warning message using v.net.distance in GRASS

I'm using GRASS 7.0.4 under Linuxmint 17.1 KDE. I need to build a raster with the shortest distance from every pixel to a city following a road. I have two shape files, the city (point) and the road ...
1
vote
1answer
27 views

Constructing a weighted graph a.k.a. a road network with distances for a specific area

Pardon my ignorance in GIS/Routing tools as I'm new to it: I have a map in OSM format and wanted to build a routable graph out of it ( to experiment a searching algorithm I have in my PhD thesis). ...
0
votes
0answers
11 views

USA Road Network Data Set Options?

I need a contiguous, nationwide USA Road Network with speed limits, distances, etc. I have been using TIGER but the challenge is at state boundaries - where contiguous road segments are split. Is ...
2
votes
2answers
45 views

ArcGIS 10.3: How to merge lines divided by junction points?

I have one shapefile with train stations (points) from a region in the UK and another shapefile with railroad tracks (lines) between these stations. Problem is, in the latter I don't have a unique ...
3
votes
1answer
42 views

Create an Origin - Destination map using roadnetwork layer

I am using Qgis 2.14.2, I am trying to create a O-D using the road network that I have in a feature. Is any way or plugin that can help me to plot 500 trips using as a path my road network layer? I ...
1
vote
1answer
27 views

Selecting parallel line segments but not segments that intersect

I have 2 different shapefiles that each have railroad track on them. Most of the track being displayed is the same, but since it is coming from 2 different sources, the physical lines themselves are ...
0
votes
1answer
24 views

Problem when building network with spatialite-gui

I would like to find the shortest path between two points in the following graph and corresponding table: I am using spatialite-gui for windows version 1.2.1 and I am having a problem when ...
14
votes
7answers
8k views

Which tools and methods can be used to create isochrones?

I'd like to get an idea for what's involved in creating isochrones for a series of sites, with a reasonable degree of accuracy to the estimates. A general outline would be great, though my scenario ...
0
votes
0answers
16 views

Finding closest feature to known point based on road layer?

I am using ArcGIS 10.2, standard I have 3 files: Facilities Storage Road I want to find the closest storage location to our facilities based on the road layer. The spatial join tool doesn't ...
3
votes
3answers
297 views

Converting 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 ...
1
vote
0answers
18 views

Automating the Road Graph “shortest path” plugin in QGIS to batch compute routes

Is anyone aware of how to automate the Road Graph "Shortest Path" plugin in QGIS, calculating multiple routes from multiple origins to multiple destinations, using two point files and road network, ...
2
votes
0answers
30 views

QGIS Broken Link to files on a server

My colleagues and I are using different versions of QGIS (2.8.2, 2.86 & 2.14) on windows 8.1 and Windows 10. When we open existing projects we get a "Handle Bad Layers" box coming up. We have ...
1
vote
0answers
48 views

Looking for an algorithm to quickly find the closest point on a road network (or other graph)

I am looking for a fast algorithm that will find the closest point on a line segment in a graph (such as a road network) to my test point. I'll try to be more specific. I have a road network graph. ...
1
vote
0answers
17 views

Qgis network prepare road graph

I have been working on finding shortest path between two buildings. For that purpose i have created kml files of various streets, converted them into shape files and then merged all of them together. ...
1
vote
1answer
16 views

QGIS, Calculate networks first, diameters second

I need to get the following task done: First, various points (stored in a shapefile, identified by a common attribute) need to be put into relation with each other (see graphical scheme, steps 1 and ...
2
votes
1answer
219 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 ...
3
votes
1answer
301 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 ...
6
votes
4answers
141 views

PostGIS query for selecting features not connected to rest of road network?

I have a dataset of roads in a city stored in a PostGIS enabled database. I would like to identify and remove any feature which is not connected to the rest of the road network. This behavior is ...
2
votes
1answer
45 views

Expand Street Network passing through points using QGIS?

I have a road network (red) passing through some traffic data points (green): I want to expand this network to include all of the points. I already have a bigger street network (blue) from which I ...
1
vote
0answers
36 views

Calculate shortest paths for each output area in catchment through road network to a single point (i.e. store)

The title sums it up pretty much. I'm looking to derive trip distributions to a single store using population data and distance within a prescribed distance catchment. I have calculated the catchment ...
2
votes
1answer
132 views

How to use the Grass modules v.net.xxxx from within QGIS

I'm trying to create a an area that can be reached within a certain amount of time/distance from a single (or multiple) points. To do this i'm using the GRASS tool v.net.iso (via the GUI). I've ...
2
votes
1answer
31 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 ...
1
vote
1answer
27 views

ArcMap 10.1 Create colored lines from one layer to another based on common field

I joined a points layer to a polygon layer. How can I draw lines from a one-to-many polygon to points? I don't have Business Analyst extension so I don't think spider diagram is the right tool. Also, ...
1
vote
0answers
16 views

QGIS-streets network: How to get the points equistant at a certain distance from one point given?

Into a network of streets (let’s suppose polilines or polygons): How to get the points equistant at a certain distance from one point given? I know how to do this with ArcGIS with Network Analyst ...
55
votes
11answers
22k 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 ...
1
vote
0answers
20 views

Nominatim installation - network flood

I've tried to install Nominatim with a planet.pnf file to a server which is hosted at Dacentec(36gb ram, 16 threads, 1x2TB 7200 RPM hard). The installation was going well, it was already indexing data ...
-1
votes
1answer
75 views

Mean centre on the roads network

I am trying to evaluate the current police stations. so I want to find the mean point of crime points in the city and compare the OD cost matrixes of the results. Is there any way to find the mean ...
0
votes
0answers
37 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 ...
2
votes
0answers
40 views

Roadnetwork_merging [closed]

I have a shapefile of a road network which has two lines to represent the two-way directions. My attribute consists of "fromnode", "Tonode", "length", "One-way" (every cell has a value of one here, ...
3
votes
1answer
59 views

QGIS: sewer system symbology

Is there any symbology set out there for sewer systems or other piped networks? The sort of elements I need to represent are: Conduits Junctions Pumps Weirs Outfalls Gates etc... There are few ...
2
votes
1answer
61 views

Creating isochrones in ArcGIS for Desktop?

Is it possible to create isochrones (lines of equal travel time to or from a certain point) in ArcGIS? I have a street network, with the streets having a speed limit attribute, and I need to create a ...
0
votes
0answers
39 views

Network Analyst line barriers have no network location?

I am using ArcGIS Network Analyst to calculate a route between two points on a road network. I have added a number of scaled cost line barriers but no matter how I mess with the settings, solving for ...
2
votes
0answers
101 views

Global shipping network datasets for download?

Does anyone know if global shipping routes for free download (preferably ESRI shapefile) exist? I would need them for my research only as a background presentation on the world image. They can be ...
1
vote
0answers
21 views

Convert a polygon grid into an edge table

I'm working on a robotics project. I've got a rectangular grid (polygon shape file) that is a navigateable/routable region (i.e. I can travel anywhere in this grid). That is I took my bounding area ...
1
vote
0answers
26 views

Build network based on shortest distance between points

Is there a way to build a network based on the shortest distances between each point of a point layer. I have occurrence data from species (as points) and want to estimate whether there are one or ...
2
votes
0answers
39 views

Create network graph from contiguous polygons in KML, or PostGIS?

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 ...
0
votes
0answers
59 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 ...
15
votes
3answers
6k views

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?
1
vote
3answers
305 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 ...
2
votes
0answers
34 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
39 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 ...
6
votes
3answers
695 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
707 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
226 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 ...
27
votes
11answers
8k 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
722 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 ...
1
vote
1answer
20 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
25 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
74 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
35 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 ...