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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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 ...
3
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0answers
73 views

How are costs returned by the pyQGIS implementation of Dijkstra calculated?

How are the costs returned by pyQGIS implementation of Dijkstra (QgsGraphAnalyzer.dijkstra) calculated? As far as I know, these costs correspond to the distance from the starting node to each of the ...
2
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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, ...
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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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3answers
304 views

Creating network datasets from OSM data in QGIS?

I am having a difficulty to use network analysis in ArcGIS because of unavailable network datasets. So, I googled it and realized that it is possible by using OpenStreetMap. However I don't know how ...
3
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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
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1answer
118 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? ...
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37 views

'D8 contributing area method' - TauDEM with QGIS

I'm using the TauDEM on Qgis to extract drainage area network from DEM. I could do it easily using the threshold method of TauDEM. Now I would like to do it using a shapefile of the inlets of the ...
2
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1answer
74 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 ...
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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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39 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 ...
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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 ...
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3answers
157 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 ...
2
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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 ...
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1answer
75 views

Mean centre on the roads network

I am trying to evaluate the current police stations. so I want to find the mean point of crime points in the city and compare the OD cost matrixes of the results. Is there any way to find the mean ...
7
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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 ...
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0answers
61 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 ...
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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 ...
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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 ...
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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 ...
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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 ...
2
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1answer
219 views

How to use GRASS v.kernel to calculate point densities along a network?

In a road network, I need to select the segments where a minimum of 5 dots occur (1 dot = 1 address) over a distance of 100 m (the image attached illustrates my question). I'm trying to use GRASS ...
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1answer
54 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
211 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
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. ...
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43 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 ...
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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 ...
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0answers
242 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
115 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 ...
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0answers
77 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
126 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 ...
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1answer
58 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 ...
3
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119 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
340 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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2answers
74 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. ...
1
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1answer
80 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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1answer
86 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 ...
0
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1answer
38 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 ...
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0answers
33 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 ...
2
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0answers
112 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
110 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
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0answers
185 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
77 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 ...
8
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0answers
174 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
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 ...
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0answers
24 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
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3answers
166 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 ...
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1answer
51 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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130 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 ...
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1answer
44 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 ...