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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1
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2answers
98 views

Error using Grass v.net

I'm trying to connect my network to a points layer with a threshold of 4500 meters. I have about 11000 or so entries in my polyline and about 24 in my points layer. I have alreday used v.distance, ...
33
votes
7answers
8k 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
2answers
275 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) ...
12
votes
6answers
1k views

What's an efficient way of detecting road junctions on a map?

I may receive maps from any source for my project, and for the C++ algorithm I'm making, it's imperative for the algorithm to know where road junctions (nodes where more than two road segments meet) ...
3
votes
2answers
198 views

Get the junction id for the roads in a network dataset

I have a network dataset with roads and junctions. I am wondering what class I can use in arcpy to extract FromJunctionId and the ToJunctionId for each road segment in the network dataset. Thanks.
2
votes
0answers
118 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 ...
6
votes
2answers
187 views

How can I turn a vector layer into a graph G = (V, E)?

I have a number of rail networks, in the form of shapefiles of the "line" type. I want to turn them into a more abstract graph format, i.e. the kind with vertices and edges, not chart-type graphs. ...
3
votes
2answers
141 views

Using the ArcGIS Local Routing Tool . . geoprocessing in the runtime

When I create a model in ArcGIS using the Network Analyst Tools, I am able to create Locations and make the Route Layer and Solve. However, I need to be able to add barriers as well as locations, ...
6
votes
1answer
381 views

How to find the shortest path within a polygon? [closed]

I am trying to find a way to calculate the shortest path from one point to another without crossing the boundaries of a polygon. I would like to do it with QGIS as I do not have access to ArcGis. It ...
3
votes
1answer
149 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 ...
-2
votes
2answers
328 views

What are non-commercial sources of road network other than OSM

I want to get the graph (Road Network) of Area of interest: Lon/Lat - Left/Bottom = -93.28587,44.9674 and Right/Top=-93.25351,44.9855 Minneapolis, MN Searching for a non-commercial source - aside ...
4
votes
1answer
148 views

How do you define rail network branch geocodes

As per the attached document I'm trying to define a rail network by providing geocodes for each rail stop, how would I define a 'stop' as a junction for a branch in the network without having to ...
2
votes
1answer
163 views

Visualizing KMZ network link in QGIS

Is it possible to open and visualize and kmz network link in QGIS. If so what are the setps involved? Thanks in advance Cheers
6
votes
3answers
863 views

Find a proper path between two nodes in a grid

This question is about finding a proper path (route) between two nodes (P,Q) in a grid (i.e., graph, network, ...). In our concept, we define a path proper (nice) if it is the most similar* to the ...
1
vote
1answer
293 views

Retrieving XY from point graphics set in WPF network (arcgis 10.0)

I have a WPF application using ArcGIS 10. In the application I can set two point by clicking on map and calculate route between them. every time I click on the map, The application creates a ...
0
votes
1answer
175 views

PostGIS Implementation of Brabyn and Skelly Road Network Travel Time Model

Is there a PostGIS implementation of the Brabyn and Skelly road network travel time model for the New Zealand road network? This model is outlined in: Brabyn L, Skelly C. Modeling population access ...
4
votes
1answer
736 views

Using QGIS calculate distance of point along a line

I have lots of points, and a road (lines) and I would like to calculate from point A to point B (the distance must route through the roads (lines). I found this QGIS calculate distance of point along ...
4
votes
1answer
483 views

Is there an open source tool for both road network analysis and geocoding?

Is there any one open source software package that can perform both road network analysis and geocoding?
4
votes
2answers
574 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 ...
1
vote
1answer
445 views

Create a Minimum Spanning Tree based on a street network (ArcView)

I hope you can help me with my network analyse problem (ArcGIS 10.0 SP2 - ArcView License) Background: I try to create a network of fiber optic cables to specific points along a street network. ...
9
votes
2answers
402 views

Generate near table for x number of neighbours using arcpy

There are 3 likely scenerios that I am trying to capture near distances for: An interchange subway station, which has 2 or more neighboring stations. That is, the station in question connects 2 or ...
4
votes
2answers
506 views

Which are the best open source tools/solutions for digitizing road networks?

I was thinking on tools/plugins for QGIS, but other good suggestions are welcome.
1
vote
0answers
250 views

Open Network Dataset with ArcObjects SDK 10.0 .NET

I develop desktop standalone application and use this code to open Network Dataset, but it fails with HRESULT on datasetContainer3.get_DatasetByName(). public static ...
3
votes
1answer
370 views

Is it possible to use Python to perform network analysis on only part of a network?

I have a large network dataset and want to perform an analysis on it which would output the start/end point, the distance between them and whether they're first, second or third (etc.) nearest ...
5
votes
1answer
580 views

Geometric Network - Listening to network feature connection changes in the IObjectClassEvents::OnChange event

I need to be able to tell when a particular type of feature, that participates in a geometric network, is having its geometry automatically modified due to the geometric network. What i mean is that ...
2
votes
1answer
213 views

Sources for California roads data

I need a California roads network suitable for building a network dataset and routing to 120 locations. It needs to at least cover the Northern half of California. 2010 Census roads need alot of ...
2
votes
1answer
286 views

Need to programmatically create Barriers in my Network Dataset

I have the following C# code to create a Network Dataset layer that I can bring into ArcMap. However, even though I am able to create a Route from the ND, I am not able to create Barriers of any kind ...
2
votes
1answer
450 views

How to integrate every single street into a network analysis?

This is my first question, but I solved problems before thanks to this great community! It is also my first time working with a network analysis (ArcMap 10) and there are some problems which haven't ...
2
votes
1answer
1k views

How to populate From Node and To Node fields for a polyline feature class? (ArcGIS 10)

I need to populate FNODE and TNODE fields for my roads dataset. I have an intersections point feature class that has unique ids, and I need each road segment to have an FNODE and TNODE value that ...
3
votes
2answers
220 views

Need an explanation on a network simplification algorithm

I try to implement the algorithm described in this paper (page 8), but there's a place that I can't understand, and the authors do not provide a more detailed explanation or pseudocode. They show how ...
6
votes
2answers
2k 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 ...
3
votes
0answers
403 views

IDatasetContainer2 CreateDataset method fails after upgrading to ArcObjects 10 [closed]

I have a Network Analyst routine that worked for 9.3 and does not work with 10. I was closely following the example at: ...
3
votes
2answers
144 views

LRS schema error in Oracle SDO_NET when validating network

I have a problem with the Oracle Spatial Network package. I'm creating NODE, LINK and PATH based on LRS. When I try the call: SELECT SDO_NET.VALIDATE_NETWORK('network_tracking') FROM DUAL then I ...
6
votes
2answers
657 views

How do I select only those features, that are connected?

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 ...
3
votes
2answers
467 views

How do you get access to a Network Analyst layer item in ArcPy?

I have a Python script that I'm working on. I have created a Closest Facility layer (in memory). I add facilities. I add incidents. I perform the Solve. These all complete. The only problem is, ...
5
votes
1answer
431 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
1k views

How can I calculate driving distance between 2 lat/long points

I want to build a .NET application that can get an input of 2 lat/long points and return an output that specified the driving distance between the points. Appreciate suggestions for API's or methods ...
5
votes
2answers
1k views

Are there any open source network analysis tools?

A researcher in my field* recently created an "Urban Network Toolbox", an ArcGIS extension built upon Network Analyst. It calculates a number of measures on urban networks, such as betweenness and ...
12
votes
3answers
660 views

PgRouting - How to clip links when reaching max costs?

I have a polyline shapefile representing a road network and a second shapefile containing points. I would like to use PostGIS (presumably PgRouting) to identify sub-networks or service areas radiating ...
8
votes
1answer
241 views

Large survey on unconnected underground networks

We (read I) are currently surveying all the stormwater pits and pipes in our shire, and have run into a few issue with handling unknown network connections. The problem is that a lot of our network ...
4
votes
1answer
1k views

How to find network distances between two sets of origins and destinations?

I'm learning how to use Network Analyst, and I'm not entirely sure what to do (or search for). My objective is to measure the nearest distance from the red circles to the blue circles along a road ...
11
votes
3answers
742 views

How to simplify a routable network?

I have a network graph that I need to simplify in the sense of reducing the number of edges. The idea would be to merge nodes that are located close together and remove the connecting short edges. ...
3
votes
2answers
175 views

Can GRASS v.net.iso split between nodes?

Can GRASS's v.net.iso module split networks between nodes on the network, i.e., if I am finding the area within a cost of 400, and there is a line segment with a cost of 800 leaving the center node, ...
3
votes
1answer
594 views

Network Analyst hierarchy routing issues. (ArcMap)

My friend and I have created a walking network. We created a network without a hierarchy evaluation and the routing worked fine, but when we added a hierarchy to the equation many routes won't solve. ...
10
votes
5answers
3k 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 ...
4
votes
1answer
675 views

Stream Gradient - Assigning points to their respective Reaches

This is a continuation of the question I initially posed here. Also, I've attached a shapefile on my db account here. I'm trying to break a stream network up into 100m reaches, assigning elevation ...
7
votes
3answers
1k views

How to compare 2 polyline datasets?

I have a network data set for footpaths which I have generated through the collation of path networks from a variety of sources. I want to compare this with another dataset which also contains a path ...
9
votes
1answer
1k views

Difference between network dataset and geometric network

In ArcGIS, what is the difference between a "network dataset" and a "geometric network"? Are there differences with what can be done with each?
3
votes
0answers
160 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 ...
5
votes
2answers
430 views

How to sum an attribute of a feature in a network along a route? (ArcGIS Network Analyst)

In the walking network that a friend and I are creating, we want to calculate an overall safety rating for each route. Each segment of our walking network has a certain safety value. We have ...