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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

Just to close this loose end, since I asked the question a new package was released called osmar which contains a vignette of how to implement shortest path algorithms in R using Open Street Map data: http://osmar.r-forge.r-project.org/ . It uses the function get.shortest.paths from the igraph package. Excellent article on this can be found here: ...


3

OSRM has an routing API that can do that. You can find the documentation for the API here. But you have to put them in the order of appearance beforehand. To route via certain coordinates list them in the query string in the order of appearance (currently limited to 25 max points and to vehicle routing only): ...


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

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

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. ...


2

Actually you can use two tools, both are easy to install on your own server. OSRM writen in C++ and Lua GraphHopper if you prefer Java


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

You should use id3 of the result instead of id2 because id3 is the edge id according to http://docs.pgrouting.org/dev/src/ksp/doc/index.html


2

You could calculate a buffer (not more than 5 meters) for the start- and endpoint of every linestring. Then, intersect the buffer with the road network. A line that doesn't intersect with the buffer is likely to be a "correct" unconnected road. However, you'll have to play with the buffer radius for satisfactory results.


2

GraphHopper (using OpenStreetMap Data) GraphHopper offers memory efficient algorithms in Java for routing on graphs. E.g. Dijkstra and A* but also optimized road routing algorithms like Contraction Hierarchies. It stands under the Apache License and is build on a large test suite. OpenStreetMap is directly supported from GraphHopper. Without ...


2

What you are looking for is called 'reverse geocoding' and is implemented e.g. with Nominatim API


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. ...


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.


2

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.


1

If you want a GUI for pgRouting, you can install the pgRoutingLayer plugin for QGIS. It provides a GUI to access pgRouting functions to compute routes. The routes can be displayed and exported to QGIS layers which you can manipulate and analyze any way you want. You can see the plugin in action in the following screenshot (panel on the right). The plugin ...


1

I have found it, it is worth having a look because I think there are not many safe route planners based on past accidents events http://opt.berkeley.edu


1

Based on a quick Google search, I believe what you're looking for is http://www.ridethecity.com It defaults to New York, but you can select from a number of major cities in the United States, Canada, France, Spain, Australia, and a couple of others. Very interesting application! And apparently (according to this question) it's driven by PgRouting.


1

You could try my routing script for QGIS Processing based on the core network analysis library. It expects a point layer and a network layer as input and returns a route between the points.:


1

What you want to do is possible, but not in the manner you're thinking. A network could generally be considered static in that the rules and restrictions for the edges are governed by single, static values. Accounting for change and time of day is another level known as Traffic. You may want to read through this ArcGIS help page for a detailed explanation, ...


1

In JOSM you can use the PicLayer plugin an load your raster image in and digitise the data into vector indoorOSM format. I will not be a 5 minute process you will have to plan a few hours into create the JOSM project and digitising will the time consuming part. http://wiki.openstreetmap.org/wiki/IndoorOSM#PicLayer JOSM is downloaded from ...


1

A possible solution could be: Modern maps show 30 or 50 km/h for situations with/without traffic. The classic map show 40 km/h as a way of representing both situations as a single number.


1

In my opinion trouble is that st_makeline function is making line from set of edges that have different directions. I'm using function ST_Union to join edges and don't have this problem. Maybe you should use this function insted.


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Using Linear Referencing of ArcGIS for Desktop the steps are: Create Routes to create routes from your polylines Make Route Event Layer to place your road signs as point events along the routes Copy Features to copy point events to a point feature class


1

Take a look at OSRM (Open Source Routing Machine). It uses contraction hierarchies, is VERY fast. It's written in C++ - but this is a small standalone server application. You could simply use a few network API calls and a JSON parser. So wouldn't add coupling to your C# application.


1

source and target attribute contain node ID's. Each node ID should be unique, but it can appear multiple times in source and target column, because a node can be the connecting point for more than one road link. Depending of the direction (defined by the geometry) of the road link the node ID is source or target.


1

jsprit can solve your problem. It is a java based, open source toolkit for solving rich traveling salesman (TSP) and vehicle routing problems (VRP). Rich means here that you can model an arbitrary number of constraints that account for your business requirements such as skills, time-windows etc.. And in conjunction with jsprit, you can use GraphHopper.


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Our RW Net 4 SDK provides support for "approach"-based routing, including optimizing the sequence (TSP) and avoiding u-turns.


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MapQuest Open Directions API Web Service has an "Optimized routing" feature: All the power of the routing function, plus we'll re-order the stops for you to provide the most efficient route to get to all your stops. Great for planning out the best way to get round multiple places you need to visit in a single journey. There is also Google Directions ...



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