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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0answers
40 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 ...
2
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2answers
26 views

Harvesting pixels using GRASS GIS

having a binary raster map of pixels of interest, a road network, and a target point, my goal is to get a raster map with network pixels having as value the number of pixels of interest they allow to ...
1
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0answers
22 views

Why are MySQL network connections extremely slow in QGIS 2.0 - 2.6 (when compared to QGIS 1.8)

In our project we have been using QGIS 1.8 Lisboa with a MySQL database placed on a server accessed via local network since two years. Everything is working fine and quick. The vector layers can be ...
2
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1answer
31 views

Is there a way to minimize turns in Network analyst routing?

I have a network of pedestrian routes and I want to provide them with clean directions but network analyst chooses the first route that it can turn towards destination and gives me a zig-zag road. Is ...
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0answers
11 views

Counting number of turns along route if global turns are defined for network? [duplicate]

I am having problems counting the number of turns, I need to minimize them for my routing purposes.
1
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0answers
6 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 ...
11
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6answers
5k 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
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0answers
26 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 ...
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1answer
45 views

Data dots aren't showing up (Cartodb)

If I connect to my campus network, the map is not showing any data dots. And from the screenshot you can see the error messages. If I use any other network, for example using my phone's hot spot ...
0
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0answers
26 views

Creating a Scaled Cost Weather Layer - Network Analyst

If anyone has created a Scaled Cost - Polygon Barriers - Network Analyst, I'd be interesting in Tips and Tricks. I'm trying to figure out how I could take a weather (or any polygon layer) REST feed ...
2
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1answer
47 views

Converting Historical Railroad Systems Data from KML?

I'm writing a paper for an undergraduate economic history class and I'm interested in North American railways in the 1800's. I've found historical GIS data for the period here. The railroad data are ...
6
votes
3answers
445 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. ...
1
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0answers
16 views

Is there a QGIS equivalent to ArcGIS's Make OD Cost Matrix Layer (Network Analyst)? [duplicate]

I'm looking to create a OD cost distance matrix for a network data set I have created. Is there a way of doing this in QGIS which is akin to Make OD Cost Matrix Layer within ArcGIS's Network Analyst. ...
6
votes
3answers
1k 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 ...
2
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0answers
138 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
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0answers
61 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 ...
1
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0answers
10 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 ...
41
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10answers
13k 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 ...
3
votes
2answers
102 views

QGIS GRASS shell commands not working in Yosemite

First time asking a question here. Running GRASS 6.4.3 within QGIS 2.4.0 on Mac OS 10.10 Yosemite. I'm trying to run v.net.iso within the GRASS shell, but the following error is returned every time: ...
0
votes
2answers
29 views

ArcGIS compute nearest network neighbour for each point

I have a set of points and I would like to calculate a value for each point to indicate how 'clustered' to other points that point is. Distance to nearest neighbour (through a network) would do fine. ...
18
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5answers
1k 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. ...
4
votes
1answer
340 views

How to create a service area using both streets and buslines in the same network?

I want to create a network analysis more difficult. Therefore, I want to calculate a Service Area around hospitals next to busstops. But: The network does not only consist of roads and ...
0
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2answers
28 views

How to calculate miles of road in street network

I have a road network we use for our city. It has ever single road created and categorized. What would I do if I wanted to calculate the total miles of roads in this network?
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0answers
136 views

Finding shortest cumulative route (i.e. best 'hub') between networked points

How do I find the shortest cumulative route (i.e. best 'hub') between networked points? I have a dataset where some but not all of the points in the network connect to each other, however it is ...
1
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0answers
28 views

Map Routing (paper route) [closed]

I am doing a undergraduate GIS project. It entails a paper route for newspapers in the Pittsburgh Area, so far I have plotted all of the points in a point layer. I have now plotted my points, what ...
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1answer
49 views

How to find the best location to put a facility within network so that all points are near a facility?

Suppose I have many points distributed in a network. I want to place three facilities in the best way so that all points are near a facility. How can I do it? Any solution and software should be fine ...
0
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1answer
52 views

Grass GIS “v.in.ogr”: How to prevent crossing lines from beeing split where they don't share a common node?

I want to import a road network into grass gis to run network analyses. I use "v.in.ogr" to import my road shapefile. The problem is that Grass GIS seems to split every crossing line no matter if they ...
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0answers
36 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
1answer
38 views

Is it possible to make stops not in a certain sequence in order to find the shortest route with the network analyst?

Is it possible to make stops not in a certain sequence in order to find the shortest route with the network analyst? I now use the small green points as an input stops because I want the lines with a ...
8
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3answers
234 views

Spatial Network Cleaning

Data used to create a network from has special considerations when cleaning, as minor spatial errors can lead to major bugs in connectivity. What techniques could be considered best practice for ...
7
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4answers
2k views

How to find dead-ends in road network using ArcGIS for Desktop or GRASS?

I'm trying to remove all the dead-end roads in a road dataset (lines) that are less than 100m long. How do I identify roads that are dead-ends (no exit)? The 100m part is easy. I know how to use ...
1
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1answer
44 views

Compute nearest points to other points using GRASS

I have a layer of address points and a layer of polling stations. My task is to determine the three closest polling stations to each address on the street network. I think that the answer is in ...
1
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0answers
36 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 ...
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1answer
40 views

How to assess quality of the TSP algorithm?

I'm trying to develop my own algorithm for solving Travelling Salesman Problem (TSP) I tested it (in its current state) on the "att48" instance of the TSPLIB and got following results: As we can ...
24
votes
10answers
5k 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 ...
3
votes
1answer
657 views

QGIS 2.2 problem, loading layer into road graph

I have the road graph plugin installed, but when I try to configure it with the Settings dialogue, no layer names appear in the Layers field. I have tried various shapefiles, but the Settings dialogue ...
2
votes
0answers
31 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 ...
1
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0answers
26 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 ...
1
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0answers
81 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 ...
3
votes
2answers
70 views

Identify all continuous networks in a dataset

I have a set of pedestrian streets for a city. I would like to assign all of the streets that can be reached to one another along a continuous network to a unique group. I am wondering if there’s an ...
0
votes
1answer
36 views

pgRouting can't find route at intersection

I have a simple path that is defined by two polylines: The first line goes from point 1 to point 2, and the second from 3 to 4. After running the pgr_createTopology script the source and target's ...
2
votes
0answers
21 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. ...
3
votes
3answers
86 views

Hierarchy not working in network analyst

I have created a simple network to test hierarchy. But apparently I am missing something. I have created an attribute for my roads called hierarchy and given it values of 1 to 3. The network is set to ...
1
vote
1answer
59 views

How to create a routable network with PGRouting

I have two sets of data Table A: Stations - contains postal code (which I can convert to lat/long), name and code. Table B: Connections - contains a possible list of connections including source, ...
3
votes
4answers
141 views

UK road network dataset

Can anybody guide me to a website or a source to download the Geographical UK road network data set. The data set should include the road distances, since I want to apply shortest path search ...
1
vote
0answers
46 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 ...
9
votes
1answer
670 views

How can I improve the speed at which QGIS 2.4 handles network data? (Seems much slower than 2.2 - even with small datasets)

I recently downloaded and installed QGIS 2.4 Chugiak on a Windows 7 64-bit machine with a quad core processor and 8GB RAM. I'm having a few problems using datasets of all sizes from a network drive - ...
-3
votes
1answer
498 views

How to extract drainage line network from GRASS GIS and QGIS [closed]

Giving DEM as input is there any way to get drainage network? I am newbie to GRASS and QGIS ,provide any working examples in GRASS GIS and QGIS with procedure.
0
votes
2answers
150 views

Shapefile to Network xml

I have a shapefile representing the US freight highway network available from Oak Ridge National Lab. I'm trying to prepare this as a .xml network for processing with MATSim. The output structure is ...
2
votes
0answers
15 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 ...