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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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
177 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
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3answers
238 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
40 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
41 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
72 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
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0answers
26 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
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0answers
17 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
67 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.
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0answers
53 views

How to find NetworkAnalysis extension with ArcObjects?

I'm using ArcGIS 10.0 My code: IAoInitialize init = new AoInitializeClass(); var a= ...
2
votes
0answers
60 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
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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
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0answers
37 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
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1answer
69 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
52 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
204 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
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0answers
44 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
33 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
271 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
154 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
92 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
102 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
792 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 ...
34
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
41 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
113 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
73 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 ...
1
vote
2answers
76 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 ...
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vote
0answers
38 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 ...
0
votes
0answers
34 views

How to create a mean centre using a network dataset

I have a set of offices, with the number of workers in each office. I need to find the mean centre of these offices weighted by the number of staff. E.g. the 'centre of gravity for staff.' I have done ...
2
votes
1answer
81 views

Image cache on network drive vs. SDE/Oracle

We currently have all of our image data loaded into ArcGIS SDE/Oracle 9.3. There is a proposal to not load our 2015 orthoimagery into SDE/Oracle in order to save time and place it in a tile cache or ...
2
votes
1answer
58 views

What is the math behind Avoid High, Medium, low in Network Analyst and can it be changed ?

When you are creating the network, in the attribute section you can define restrictions. Of such restrictions are Avoid High,Medium, Low and Prefer High, Medium, Low can someone mathematically explain ...
7
votes
1answer
189 views

Visualizing road Intersections & connections in ArcGIS

I am working with polylines (roads) in ArcGIS and I was wondering if there is a possibility to somehow show intersections as well as connecting parts of all the different road-segments. Also, would ...
1
vote
0answers
60 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 ...
4
votes
1answer
4k views

How to find the watershed area for each point in the river network using DEM?

Update#1: Thanks, Micha, I have followed your instruction and successfully use the modules in GRASS. I use r.watershed to get the basin raster and the drainage line: and I use r.water.outlet to get ...
0
votes
0answers
85 views

Why does cascaded WMS not work? (Geoserver)

I run a Geoserver installment as a service on a Windows Server 2008 R2 machine. I try to add a WMS source but everytime I get timeout-exception. As I need to use a proxy I edited wrapper.conf as ...
1
vote
0answers
83 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 ...
5
votes
2answers
930 views

How to find the watershed for each outlet point and sum values within it?

I have the following files to work with: Stream network of a basin; Outlet points for each segment* of the network and Points which represent water withdrawals along of the stream, which are not ...
0
votes
0answers
33 views

Creating pathway using ArcGIS Network Analyst?

I have 13,086 points and 1,034 lines that go from each point to a polygon. I am trying to figure out a way to get a line the that goes from each individual point to the polygons along the lines I ...
1
vote
0answers
76 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
1answer
51 views

PgRouting: Target vertex error

I'm trying to make a matrix that shows the cost from a node to the rest of the nodes in a network. The final result I'm looking for is not the cost, but only know if a car can or can not reach each ...
0
votes
1answer
82 views

Calculate distance between two coordinates along lines

I have a map with two layers: a map of the streets of Montevideo, and a map of shops with the lat long location. I would like to calculate the distance between each shop and the nearest one, along the ...
1
vote
1answer
210 views

Geometric Network Find Upstream

I am New to Geometric Networks. I need to build a river network and find all locations (polygons) upstream. This is the template I am trying to use. I have my rivers with to and from node and the ...
0
votes
1answer
101 views

Calculating Distance and Time on a network without the use of ArcGIS Network Analyst

I'm trying to calculate a distance and time for walking commuters (about 30,000 records) on a street network (NYC Lion). I have a starting and ending address for each record that have been geocoded. ...
1
vote
0answers
42 views

How to reconstruct a network with multipart edges to a network with singlepart edges

I have a network shapefile that between its vertices , there are edges that have multiple geometric objects. When I try to node it in postgis, it creates multiple segments in the database that ...
1
vote
0answers
238 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
1answer
71 views

Once route is solved, also return encountered barriers from ArcGIS Server Network Analysis?

I have came across an unexpected "issue" while working with the Esri JS API and ArcGIS Server Network Analysis service. Once user submits the route solving task to the server, I'm appending the ...
0
votes
1answer
114 views

Can DARP be used for Non Emergency Medical Transportation problems?

I have a Non-Emergency Medical Transportation (NEMT) business and am looking for the best solution that can automate the dispatching process. I looked over DARP and it seems fine. I need to know 2 ...
4
votes
1answer
353 views

How to create a multimodal network?

How to add waterways and railroads without turn restrictions into the previously created street network dataset with turn restrictions, in order to create a multimodal network? For a university ...