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14

If you are mostly interested in traversal/routing, go with pgRouting. If you don't find what you need to do there, networkx has a freakishly large number of algorithms for graphs and now loads shapefiles out-of-the-box using OGR. nx_spatial extends networkx in some minor ways mostly related to utility networks.


14

The Feature To Line (Data Management) geoprocessing tool can be used for 'cleaning up' the data. The help file mentions: Where input lines or polygon boundaries touch, cross, or overlap each other at locations other than their start and end vertices, they will be split at those intersections; each of the split lines will become an output line ...


9

There is more than one solution to this problem. This is a way that I would recommend:. Assuming ArcMap is your primary tool: Open the attribute table of the network source features. Add a field of type "Short" (any integer type will do). This will effectively be a boolean value. Give it a name that would describe it as a restriction. For each road ...


8

In ArcGIS 10, the default number of features returned by an ArcGIS Service for queries (identify/find/query) is 1000, though yours could have been set to 500. You will need to change the service properties in order to increase the maximum number of results. You can do that by stopping the map service, going to Service Properties - Parameters tab, and ...


7

You might want to browse this post: Alternatives to pgRouting and look through the previous posts using the Network and Routing tags


6

The question has been asked before on Stack Overflow: Find all paths between two graph nodes; and Graph Algorithm To Find All Connections Between Two Arbitrary Vertices


6

Since you are on ArcGIS, here it goes.. Skills: I suggest starting with learning basics of Network Analyst (further NA). It is impossible to get started preparing the data for network analysis withouth understanding of the basics of the GIS routing and network analysis theory (graphs, edges, junctions, cost, algorithms). Industry: a good place to start is ...


6

As far as I know it's not possible to solve for alternate routes without some additional input or change to the analysis. In a network, given a particular impedance, there is only one shortest route between two points. As soon as you start looking for alternates without any additional input you've essentially removed the 'shortest' constraint and are back to ...


5

spatiaite has routing capabiliies with a GUI. I have never tried it. http://www.gaia-gis.it/spatialite/spatialite-network-2.3.1.html /Nicklas


5

The GUID for INALayer is 667B776B-5905-4450-9C94-18B214ECE8FB. This can be found in the registry by performing a search in RegEdit or programatically: typeof(INALayer).GUID.ToString()


5

Firstly, I am not clear on what kind of output you expect. Do the red and blue vertices consist of pairs? (i.e. do you want the shortest path from one of the red vertex to a specific blue Vertex?) You should have a look at creating shortest routes This requires all the stops that you route must past through. So assuming that your requirement is the shortest ...


5

As the error says, you have problems with the network dataset itself not the Route layer or solving the model. I'd try several things: 1) Add a network dataset to ArcMap and when prompted do not add any source features. Does it draw correctly and has edges? If yes, then the network dataset has been built properly. Try running a simple test of routing ...


5

You can use the Planarize Lines tool in ArcGIS (ArcEditor or ArcInfo license is required). Keep in mind though that you would lose the overpass/underpass information in this case since all the intersecting lines will be splitted. More general reading on splitting lines is available here.


5

If your facilities and incidents are both feature layers, and you only care about finding the closest (and not 2nd closest, 3rd closest, etc.) then you can just run Spatial Join. Set your incidents as the target_features, facilities as join_features, and closest as the match_option, and it will join the attributes of the nearest facility to each incident.


5

You Network Dataset requires the Cost/Attribute in the Function Evaluator (when building your network) You can see here there are 4 types of attribute (Minutes will build your drive time analysis buffers) See Types of evaluators used by a network ...


5

You could try the Identity tool, using your line features as the input, and polygons as the identity features: "When the Input Features are lines and the Identity Features are polygons, and the Keep relationships parameter is checked (relationship set to KEEP_RELATIONSHIPS), the output line feature class will have two additional fields, LEFT_poly and ...


5

A network dataset must reside within a feature dataset. A feature dataset can be created in either a file geodatabase (folder.gdb) or a personal geodatabase (filename.mdb). You can't create one in a shapefile, if that's what you mean by 'normal'. Note you'll need to add the street layer to the network dataset in order to build a network from it, and there ...


4

I see from your tags that you are running ArcGIS 10. I've used the following method for a similar task: 1) Use Multipart to Single Part 2) Use Unsplit In order for this to work (i.e. so that you have the lines in the proper order) you may need to break the line into the constituent end points and then change the direction based on an attribute (e.g. 1 = ...


4

This problem is one of optimization. As such, let's express the objective and the constraints. I will formulate this in a dual manner: rather than thinking of the objective as achieving full coverage of the network, let's consider this as a constraint and make the objective be that of minimizing the total cost to achieve that coverage. Thus, the objective ...


4

Use PgRouting. PgRouting works with PostGIS and so it falls into your category of "another OS GIS". Underdark has created a whole suite of tutorials (including installation instructions) here. A search on this site for pgrouting will generate a lot of other discussion, links and tips.


4

You can use the Make Service Area Layer, Add Locations, Solve, and Save to layer file geoprocessing tools to generate service areas for multiple input features (e.g. a point layer with geocoded addresses). This is analagous to the workflow using the ArcMap GUI described in the Service area analysis help topic.


4

So here is what I would Find out: Is your License valid, and not expired? To see this go to Start>>ArcGIS>>Desktop Administrator and go to the Availability Section. You will see how many ArcGIS Network Analyst extension licenses are available on your License Server, and how many are free. It will also indicate the expiry date of the License. In ArcCatalog ...


4

This is an instance of a shortest path problem: given a set S of polygonal "obstacles" (considered as open point sets), a start point p, and an end point q, to find a shortest path from p to q that does not intersect the interior of S. Such problems are solved by first constructing the "visibility graph" of S. One first proves that any shortest path from p ...


4

Here is the step-by-step tutorial on how to calculate Service Areas. If you want to run the same analysis but several times providing multiple values for the operation, you might consider using the Make Service Area Layer and the Solve GP tools. There is a separate tutorial on this, too. If you need to build anything more advanced, consider using the ...


4

You cannot create a network dataset with arcpy at this time. Your option is to use ArcObjects. There is a Street Data Processing toolbox that is built on .NET by Esri (the source code is provided), which you might modify to meet your business workflows. A GP tool which is part of the toolbox creates a network dataset with certain user-defined parameters, so ...


4

I think some of the answer depends on the layout of the road network, and this question might be worth posting on the Math Stack Exchange (http://math.stackexchange.com/) as it seems like a graph theory problem. I don't think this will be the optimal solution, but it might help get you closer. You could divide up the road network into natural regions, ...


4

Esri's free ArcHydro Extension will do this ArcHydro page. Download from there or Download. Once installed, load shapefile. From ArcHydro select Attribute Tools > Generate From/To Node for Lines. This will generate FROM_Node & To_Node columns.


4

If you want Free (but you will have to do a lot more pre-processing) OS VectorMap™ District is available. https://www.ordnancesurvey.co.uk/opendatadownload/products.html For commercial rotatable data you have 3 options. Ordnance Survey - OS MasterMap® Integrated Transport Network™(ITN) ...


4

My solution to this was kind of a kludge, but then I was doing a small class project working with a subset of one county's roads so the network wasn't that big and I didn't need to do it as a common task. I just ran a service area analysis with the time set large enough that in theory everything should be reachable. That highlighted everything that was ...


4

You should use the Reorder Stops To Find Optimal Route option. By default, a route traverses stops in the order you define. However, you can possibly shorten the route further by letting Network Analyst find the best order. It will account for a variety of variables, such as time windows. Another option is to preserve the origin and destination ...



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