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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16 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 ...
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1answer
34 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 ...
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1answer
41 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 ...
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1answer
40 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. ...
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0answers
32 views

Routing problems with Network Analysis [closed]

I am merging several counties into one feature class and creating a network analysis dataset for routing. However, I have one particular county that I can't get routes for. I have checked topology, ...
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6answers
6k 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
37 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 ...
3
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1answer
538 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 ...
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0answers
51 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 ...
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1answer
42 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 ...
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1answer
49 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 ...
3
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1answer
275 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 ...
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0answers
36 views

GRASS in QGIS: Problem with creating isolines from points

I'm quite new with GIS and hope, anybody can help me here: I try to create isolines from service points by using GRASS in QGIS 2.8.2. After connecting the road network (based on OSM data) with 45 ...
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0answers
57 views

What is the reason for the very poor performance of ESRI's file geodatabases on network drives?

I am asking this question because I am at a loss and dont have a good enough understanding of all the underlying operations going on 'under the hood' of Windows/Arcgis. What is the root cause of ...
1
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2answers
52 views

Simple way to share maps on a network drive?

I am not an expert in web GIS and I would like to share some maps I created with non GIS aware colleagues from other offices. I have looked at various options but I can't find one that suits my needs. ...
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1answer
28 views

Best way to filter points given a starting point and max travel time

I have a database of about 1M geolocated addresses and I'm looking for a way to sort/filter these records based on a starting point and max travel time. Ex: "find every baker shop within 30 min ...
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0answers
43 views

Steiner tree problem: Optimal routes for Fibre planning on road network

I am trying to solve a large optimization problem where I have a set of nodes on a road network that need to be connected using fibre using the shortest possible amount of fibre. The problem is a ...
3
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2answers
123 views

ArcGIS tool for graph analysis

I have a road network shape file. After creating Network dataset I get a graph with vertices and edges. I need to create a tool for ArcGIS (through a Python code) which enables to calculate depth of ...
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0answers
135 views

Can GRASS compute the line graph representation of an input graph?

I'm interested in computing a line graph for an input graph, preferably in GRASS since I'll be using other GRASS network analysis tools afterwards. I couldn't find any reference to line graphs in the ...
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1answer
36 views

Using Copy Traversed Features to count turns for a route result in Network Analyst

I have the output of the route layer. And I want to determine the number of right and left turns for each route. For that, I used the COPY TRAVERSED ROUTE FEATURES tool from Network Analyst. However, ...
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0answers
75 views

Finding number of left and right turns for each shortest route

I have a network dataset for a city. I have, lets say, 200 trips that are made in that city. I constructed the shortest route for the every pair of the trips, and also the actual route travelled by ...
0
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0answers
50 views

How to do NETWORK kernel density in ArcMap for road crashes?

I wish to know steps to be followed for carrying out NETWORK Kernel Density Estimation (KDE) in ArcMap (Arc GIS 10) for point events (road crashes). In ArcGIS 10, there is command do kernel density ...
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1answer
44 views

Python script to accumulate flow volumes for a pipeline geometric network

I have a point wells layer and a polyline pipeline layer. The wells are snapped to the end of the pipeline segments. The wells layer has weekly updated flow volumes and I'd like to find a way to ...
4
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1answer
63 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 ...
0
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1answer
25 views

Creating network in ArcMap from an RGB image to find optimal path between locations?

I am hoping to find optimal routes from an Origin (car park) to destinations (Library, Blocks, Rec Center). I have an RGB ortho-mosiac image taken from an UAV that I want to digitize paths, car ...
3
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2answers
327 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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0answers
28 views

An algorithm that could find a random cycle in a graph

I am looking for an algorithm that could find a random cycle in a graph from a node while that cycle is traversing around another nodes (area). For example, from the green star on the left of the ...
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0answers
35 views

Set destination address using Esri Directions

I am using the sample on the Esri JS API and would like to set the destination of the directions to always be my address; any idea how to do that? The code to do this is: <!DOCTYPE html> ...
0
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0answers
29 views

Is there any way to add the Origin ID in the isolines calculations (GRASS GIS)?

I would like to ask whether there is anyway in to add the OriginID in the calculations of the Isolines (v.net.iso) in GRASS Gis. The calculations are a bit useless if they only include the cost ...
0
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1answer
18 views

What causes v.net connect “Failed to find intersection segment” and how to fix it?

In GRASS 7, when running v.net connect, I get the ERROR: Failed to find intersection segment and no output is generated. The only mention of this error Google found is in the source of connect.c What ...
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0answers
40 views

Calculating driving distances from a number of post codes to a number of services using QGIS

I am hoping to calculate the driving distance from a large number of post codes to their nearest service. I have used the RoadGraph plugin but this only calculates the distance and time from one ...
3
votes
0answers
106 views

Is it possible to create Isochrones in QGIS GUI?

I'm new to QGIS and have tried to create isochrones around points for quite some time. Is there any option to create isochrones on the GUI in QGIS? I know how to create them using pgAdmin (using eg ...
0
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1answer
55 views

Nearest intersections outside the polygon in ArcGIS for Desktop?

I have two layers, a street network and a polygon, and I want to find the nearest street intersection points just outside the boundary of the polygon. For example some area is closed by police and I ...
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0answers
17 views

Capping the amount of a certain cost per route with Network Analyst

With the Network Analyst extension in ArcGIS 10.2, is there a way to set the maximum amount of a certain cost that a route must not exceed? For example, can I require routes to be below a certain ...
6
votes
3answers
98 views

Shortest Path Analysis with Turns

Problem: Using FME and a road networks dataset, I am trying to find the shortest path from A to B, while taking into consideration of turning width (say for a truck). I have created a point feature ...
1
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1answer
116 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 ...
2
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0answers
102 views

How to build a GRASS network with node IDs from the line dataset?

I have a dataset of street network links (line geometries). Each network link has a link id, start node id, and end node id attribute. I want to use this network in GRASS, so after importing the ...
1
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1answer
35 views

Setting junction properties in ArcGIS Desktop?

I have a situation where I have a line feature class and need to build a network out of it. The lines represent roads. I wonder how I can model the intersections on the network. Almost all of them ...
2
votes
0answers
32 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 ...
12
votes
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) ...
2
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1answer
67 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 ...
0
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0answers
56 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 ...
0
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0answers
32 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 ...
43
votes
10answers
16k 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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0answers
105 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
votes
2answers
30 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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0answers
36 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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0answers
42 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
52 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
40 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 ...