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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 ...


3

Yes, you can do this with pgRouting. As a starting point I would recommend you to look at the pgRouting Workshop. Most efficient for your case might be the one-to-many shortest path funtion named kDijkstra. You could import your node-pairs into a PostgreSQL database or just write a small application that reads the CSV file and then runs the SQL queries. ...


3

At the moment, I could only easily find data for the UK: http://data.dft.gov.uk/gb-traffic-matrix/Raw_count_data_major_roads.zip It's in .csv format so you can manipulate it in Excel or by using other softwares (much easier than pdf's!). It also contains coordinates to immediately import the points into GIS software (tested this successfully with QGIS). ...


3

ST_StartPoint() only accepts LineString as input. You'll have to strip your table down from MultiLineString to LineString, either by taking only the first element up each geometry ALTER TABLE foo ALTER COLUMN geom TYPE Geometry(LineString,4326) USING ST_GeometryN(geom,1) Or, more correctly, dumping the multis out, in case there are legit multis. ...


3

It may seem like laziness on the part of Watershed tool developers to stick with the simplest and oldest flow algorithm, D8, but there is a very sound reason for doing so. The difference between the D8/Rho8 flow algorithm and the more advanced algorithms that you mention (e.g. D-infinity) is mainly in their inability to represent the dispersion of overland ...


3

One possibility would be to use a turns feature class or table to model an increased time impedance for all turns. The idea would be to use a high value for turns (such as 15-20) seconds, and a low impedance for straights (0-5). Then, as routes are created, every time a turn is the "fastest route", the additional impedance time will likely influence the ...


3

You can use OpenRouteService to add custom avoid areas / danger zones etc. The only alternative seems to be BRouter corresponding to the wiki overview.


2

I believe the software you are looking for is called "BP Distance Tables". It is a very easy to use program that does not require you to enter all the waypoints. You simply enter the starting and ending ports and in some cases you select the preferred route. The program does the rest. It is used by many ships to roughly plan their route. It gives them ...


2

Have you done the pgRouting workshop? The workshop should clarify the following: There are import tools for OSM data, so the network will contain the routing topology already after import. If you still want to use SHP files, then it explains how. Your bus stops have coordinates, so you just need to start from the nearest point in your road network. ...


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osrm-isochrone is a small node.js library for generating drivetimes.


2

Works for me in QGIS 2.6 with Processing 2.6 (on Win7) and the test data Spatialite file from the repository. If you are using different data, please share it. Check if network and points are in the same CRS.


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What you should look for is called 'Map Matching'. I've opened sourced my idea based on GraphHopper very recently here so it is still in a VERY early shape, please give feedback via providing data or creating issues etc.


2

So here are the code and summary of the aforementioned bugs, as requested by @Chris W. Basically they seem to refer to the same issue and to have the same cause, i.e. a problem with the OD cost algorithm. NIM094092 - The OD cost matrix analysis in ArcMap returns different travel time results for one origin if another origin is present. NIM060948 - Time and ...


2

I can answer the 2nd part of your question, the first one has me a little tied up now too I'll edit if no one answers when I get my head around it. So for 2) just use something in the line of routeControl._routes[0].summary.totalDistance See if this works, also _routes[0] represents your choice for example if you have another routing option for which you ...


2

You can use the pgRouting function pgr_nodeNetwork, which will create nodes at intersections of linestrings. So in your case it will split the linestring into two geometries. But there is a danger that intersections, that should not be connected (ie. over- or under-passes), will also get broken into two segments.


2

GPS Visualizer will take a Google Map route (url) and convert to .gpx "You can ignore most the options, just select Gpx and paste the Google Maps URL into the box labelled “provide the URL of a file on the Web” and then press the Convert button" http://www.gpsvisualizer.com/convert_input Guide ...


1

ArcMap should do this for you automatically (snap off-network points to the nearest spot on the network) when you load locations into your analysis layer using the Network Analyst toolbar. If you need more control over which classes get locations snapped to them, you can do this in the "Layer Properties" window of your network analysis layer. See "Search ...


1

Ok so you have a field called "tt" which is your travel times, lets assume they represent whole hours. When you are building your network you'll get to the stage of specifying your attributes, default is length. At this point you add a new a attribute, see image below. Having added it right click on it and select Evaluators and set the type to field and ...


1

Some good software for this purpose is TauDEM (Terrain Analysis Using Digital Elevation Models). Main page, with info, publications, and downloads for command tools and optional ArcGIS Toolbox interface Source code on GitHub The software uses both D8 and so-called D-infinity (D∞) flow models, which is best illustrated on Fig. 1 of Tesfa et al. (2011). ...


1

Figured it out. Turns out if your Route has an EarliestStartTime it must also have a LatestStartTime.


1

Also, look under the advanced settings tab. There, you can set the importance of Time-Window Violations, which can increase or decrease travel time depending on your choice, whether you want to reach locations on time, or service more locations within the time frame. There is also an Excess Transit Time, set to high, the solver tries to find a solution ...


1

That script won't work in the latest version of QGIS as the Processing framework has been reworked and some scripts may have been broken. Maybe you will be lucky, you could try to change line 17 (as below): from processing.tools.vector import VectorWriter


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You can try jsprit. If you determine the time windows where both drivers meet each other at a specified location a priori, then it is easy to model (just look at the 'Simple Example' in the wiki to figure out how you model and solve such a problem). Time windows are defined as follows: ...


1

The way that I would try to answer your original question is to add a field to your roads and update it with a count of vertices. Add a Long Integer field Calculate that field using the Python parser to be equal to !shape.pointcount!, You can then use the vertex count field as, or to contribute to, your impedance field. You'll need to think about ...


1

If you have a well made road graph shape (with from and to nodes), you can use my qgis processing scripts at https://github.com/chourmo/QGIS-Transit-tools For batch starting points, use Shortest-times car If you want to find times from start to end, make a lines files and use Shortest-path car


1

You can find multiple versions of routing scripts which use the QGIS network analysis library in my Github repository, e.g. https://github.com/anitagraser/QGIS-Processing-tools/blob/master/2.2/scripts/point_layer_to_route.py which converts an ordered set of points into a route. None of the scripts use the intersections of an input line with the network. ...


1

If you are into Java and want Flexibility, Graphhopper is an excellent alternative. Peter, the project lead, actively encourages extensions and changes and the community is very responsive. Graphhopper works differently to Pgrouting (I use both) and it is extremely fast. Instead of using a PostGis database, Graphhopper builds its graphs direct form the .pbf ...


1

Since you appear to use a vector representation of the routes, you may first split it into short segments (in order to later have a representative view on slope etc), using v.split; then add a new column to the attribute table of that road map: "slope double precision" using v.db.addcolumn; eventually upload the respective road segment slopes to the ...


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Have you followed the guidelines on these pages? http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000057000000 http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004700000020000000 "Using hierarchy by default As long as the network dataset has a hierarchy attribute, you can set any network analysis layer you create to use ...


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@Adrian, I am really unfamiliar with the pgrouting results, however the documentation is very detailed. My answer is based on a two-step function, which will be very inneficient in SQL but [likely] produces the results. This [untested] solution will NOT optimize which is the best starting point, but will reduce the entire route network to only the edges ...



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