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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3k 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 ...
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2answers
1k 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, ...
4
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2answers
264 views

Can ArcHydro tools be used on a network in an SDE enterprise geodatabase?

Most of the documentation for ArcHydro tools discusses their use on data in ESRI's personal and file geodatabases. Is it possible to use ArcHydro tools to set network flow direction on a networked ...
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1answer
483 views

how to create a network from gps tracks?

I'm trying to build a network from several GPS-trakcs, to digitalize hiking routes on my land. I have several GPX-files from routes I've tracked with the gps. I managed to display them in Arcmap ...
4
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1answer
2k views

How to assign node IDs to links in a network?

I have two shapefile layers in ArcGIS for Desktop 10. I have one line layer and node layer. My node layer(shp) has a "code_1" field and line layer has a "code_node" field. The intersection point ...
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2answers
71 views

How do I create blocks from a road network?

I have a road network and for every enclosed area within the network I want to create a polygon that represents that area. How does one do this?
4
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1answer
895 views

Assigning points to their respective Reaches using Stream Gradient?

This is a continuation of the question I initially posed here. Also, I've attached a shapefile on my Drop Box account here. I'm trying to break a stream network up into 100m reaches, assigning ...
4
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2answers
208 views

Transportation representation Standard on roads

Is there a GIS standard to display transportation specific information in GIS databases. The information I'm interested in are: Road Directionality Center turning lanes Ramps / Bridges / Over or ...
4
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1answer
3k views

How to find the watershed area for each point in the river network using DEM?

Update#1: Thanks, Micha, I have followed your instruction and successfully use the modules in GRASS. I use r.watershed to get the basin raster and the drainage line: and I use r.water.outlet to get ...
4
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1answer
330 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 ...
4
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1answer
718 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
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1answer
331 views

PostGIS table to network analysis

I use PostGIS 2.0 and Python API (GeoAlchemy) to work with it. I want to convert topological informations (points, lines, faces) from PostGIS tables to topological network (points, lines) to study it ...
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1answer
168 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 ...
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1answer
372 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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0answers
21 views

“Merging” 2 layers of LineString with splits at intersections

I would like to "merge" 2 networks of lines and these lines need to be split when they intersect. With pictures it should be clearer : What to do: if a black line intersects a red line, they ...
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votes
2answers
721 views

Does pgRouting support turn-by-turn routing? [duplicate]

I have route list as result of pgRouting with street names. How to get messages "Turn left", "Go along" etc ... Can pgRouting do this or I need some other source and which?
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3answers
264 views

How to convert Midpoint of Polyline into Point Feature using ArcPy?

I am trying to write a python script to determine flow direction on a water pipe network. I've used this script to find the mid point along each polyline, now i need to convert this data into a point ...
3
votes
2answers
597 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. ...
3
votes
3answers
2k views

Design fiberoptic network in QGIS?

I'm a GIS newbie trying to design a fiberoptic network in QGIS. What I'd ideally need is to draw lines on top of a map or orthophoto, assign a name/id to each line and a type. Get a list of all the ...
3
votes
2answers
261 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 ...
3
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4answers
258 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 ...
3
votes
2answers
338 views

Create network from shapefile without ArcGIS?

I want to perform shortest-path analysis on a network whose edges represent real-world roads and whose nodes are buildings or other locations. I have the shapefile for the area I'm interested in. ...
3
votes
2answers
262 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, ...
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2answers
296 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: ...
3
votes
2answers
108 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 ...
3
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1answer
1k views

Read and Export OSM Road Data as a Network of Road Segments [Adjacency Matrices]

I wish to extract from an OSM file a road network, and export it as an array (adjacency matrix) where the nodes are the road intersections and the edges represent the road segments. I don't want to ...
3
votes
2answers
1k views

Map walking distance/time from transit stops

I'm working in QGIS and would like to show how far from a bus stop a pedestrian could walk along the street network in any direction for a specified set of walking times (5,10,20 mins etc). I have my ...
3
votes
2answers
207 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 ...
3
votes
1answer
186 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 ...
3
votes
1answer
294 views

Split lines at intersections in PostGIS (must be simple but…)

I'm usually closer to my answer than now, but I've looked at all the answers here and couldn't adapt one to work on my data and I'm stuck. I have oriented polylines (Montreal's train network) and ...
3
votes
1answer
930 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 ...
3
votes
1answer
180 views

Finding Network overshoots under a certain distance

we have a large contiguous network that will have legitimate overshoots (like a dead end street), but may or may not have illegitimate overshoots. Using FME, I can't seem to manufacture a way to find ...
3
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2answers
254 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, ...
3
votes
1answer
625 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 ...
3
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2answers
305 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 ...
3
votes
1answer
114 views

Calculating shortest paths from all points in one layer to any points in another via road layer in QGIS?

I'm trying to calculate the shortest paths from all the points in a layer representing population settlements (the green points) to any of the points in another layer representing the hospitals ...
3
votes
1answer
226 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 ...
3
votes
3answers
237 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 ...
3
votes
1answer
988 views

How to get the distances (shortest path) between all pairs of points in the river network?

I have 2 vector shapefiles (one line, one point), and I have tried at least 4 ways to try to get the distance matrix at one time (and most concern the directions of each river segment) quantum ...
3
votes
1answer
856 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. ...
3
votes
1answer
308 views

determine the closest points on the network?

In ArcGIS, I have only a point layer relating to a hydrography network's pour points. Now I want to write code in VBA that selects a point from this layer, then highlight the closest points to this ...
3
votes
0answers
27 views

Calculating a specific distance from points along a network - GRASS

I'm currently using the v.net.iso function in GRASS (no access to network analyst in ArcMap). Does anybody know of a way to export the result to shapefile so that you have an individual line ...
3
votes
1answer
31 views

Get upstream sections of a network

Is there any extension to get all upstream sections of a polyline shapefile which represent an hydrographic network in QGIS? It could work like this: you choose a specific branch and a direction ...
3
votes
0answers
55 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 ...
3
votes
1answer
31 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 ...
3
votes
0answers
85 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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0answers
157 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 ...
3
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0answers
82 views

How to find the minimum number of inspection points?

I am working on a pipeline inspection project and there is a high liklihood that some inspection tool deployment/retrival station will need to be installed on the pipe network. the problem is ...
3
votes
0answers
128 views

District heating expansion design with ArcGIS [closed]

I am quite new at GIS but I have some experience of the basic concepts involved in a workflow of them. What I currently want to do is to calculate the cost of expanding an existing district heating ...
3
votes
0answers
165 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 ...