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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Taking photos representing concepts of scale, territory, flow and network in relation to globalization? [on hold]

For my assignment, I have to take four photos representing each of these concepts in relation to the processes of globalization. I've read my textbook, but I don't know what to take photos of. Any ...
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30 views

What GIS tools can calculate stream/flow path travel time? [on hold]

Does anyone use GIs tools to analyze travel time along an identified stream or channel network? If so, which ones do you use? Assume that the network links or flowlines have velocity information as ...
2
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0answers
29 views

Nearest Neighbor Based on Network of Lines in QGIS [duplicate]

Is it possible to incorporate a network into the MMQGIS hub distance analysis? Essentially I have a point shapefile with zip code centroids and I'd like to determine the closest shipping hub (also ...
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6answers
2k 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) ...
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1answer
38 views

Collapse multiple lines into a single line

I need to create a route (line) feature class from another feature class that contains multiple lines making up the same route. pic 1 shows the original feature class with the multiple lines. pic ...
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34 views

Extract unique overlapping/coincident polyline routes into their own selectable layers?

I am currently working with a road network that was created in Citilabs' Viper, consisting of nodes and links. For every single link in the dataset, there is an AB node for both directions, opposing ...
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2answers
183 views

How do you remove isolated roads from a bigger network?

I'm trying to perform an OD Cost Matrix calculation on a set of points using a road network from OpenStreetMap data. The network contains lots of roads that don't connect to the rest of the network. ...
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16 views

road network construction using latitude longitude and timestamp

I have gps data(latitude,longitude and timestamp) of a city over a month I want to use some routing algorithms on that data so need to construct road network or graph So how to construct road network ...
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26 views

How to do Network Kernel Density Estimation Analysis in ArcGIS?

I am looking at doing some analysis of road traffic collisions. Obviously collisions occur on stretch of roads and I was reseraching the best methodology to take into account the network element of ...
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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 ...
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59 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 ...
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2answers
27 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 ...
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38 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 ...
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1answer
35 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
10 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 ...
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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 ...
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0answers
30 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
46 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 ...
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0answers
32 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 ...
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1answer
52 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 ...
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3answers
488 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. ...
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0answers
17 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. ...
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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 ...
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141 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 ...
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78 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 ...
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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 ...
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2answers
123 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: ...
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2answers
34 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. ...
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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. ...
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1answer
344 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 ...
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2answers
30 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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144 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 ...
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33 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
54 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 ...
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1answer
54 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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39 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 ...
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1answer
41 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 ...
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3answers
238 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 ...
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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 ...
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1answer
45 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 ...
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0answers
38 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
41 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 ...
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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
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1answer
682 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
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0answers
36 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 ...
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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 ...
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0answers
87 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
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2answers
73 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 ...
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1answer
42 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 ...
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0answers
23 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. ...