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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 ...


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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): ...


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You have not specified any mobile platform so i am answering here for the most popular android platform. If you want to render the map in android device you can then use mapsforge library. There is a plugin for osmosis called mapwriter that will help you convert the .osm data into .map data which can be rendered using the mapsforge library. .map is a binary ...


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I've had a lot of success with the Mapsforge library. They have writer that is a plugin to osmosis. They have a Compact file format for fast on-device rendering of OpenStreetMap data. There is an aligned project for routing, Graphhopper, which I've found to be quite user friendly.


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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: ...


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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). ...


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I think GeoMajas is a good choice. For routing purposes I want to introduce you Graphhopper. It's still a young project, but it's java, it's incredibly fast and there are ready to use applications to route either on a web server or on the mobile device itself based on openstreetmap data. So if you have no problems to use openstreetmap and want to route on a ...


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You might want to look at OpenTripPlanner. There's an instance set up here that includes the MTA GTFS feeds. It was built with the transit index included, which can be queried via its API to find the nearest stops. The API can also be queried to plan trips. An example query, to find stops near a point: ...


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You just need to execute desired shortest path algorithm twice, first from 1 to 2 and second from 2 to 3.


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I assume that you did a copy parallel equally on the left and the right of your original roads. So, in order to clean up a bit, you could create a buffer polygon of the same size and dissolve all the boundaries. Because you have advanced licence, you can set up flat ends, it will be nicer in your case) Use "feature to line" with your lines in order to ...


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Calculate the distance to all origin points, select the 90% nearest and then do a convex hull calculation to get the catchment area. Exact steps depend upon your software.


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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


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id2 59721224 for example is the edge that connects vertex IDs 2 and 3. That's why the last record has a value of -1. Edge ID is the id you specify in the first argument (SQL query) of the pgr_dijkstra function. In your case it's the gid of the table named wp_norway_network1. Because pgr_dijkstra requires the column name id, you had to write gid AS id.


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


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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 ...


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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.


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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.:


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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, ...


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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 ...


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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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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.


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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.


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As for your question "Can a routing service take polygon geometry (for stops)?" the answer is ,no, it cannot. You have to send in the points as stops (not polygons). To solve the problem of your web application not returning anything, there are different restriction that apply to a service, some of which can be modified in the route request. For example, ...


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We had similar requirements when looking for a Maps API for our OpenTripPlanner for Android open-source project, and we decided to go with Android Maps API v2. Android Maps API v2 provides 3D camera control and 3D building renderings out-of-the-box, so you can easily create views like this: Android Maps API v2 was feature/performance-wise far beyond ...


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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


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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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I ran into the same problem this week, and eventually installed QGIS 1.8 (didn't even need to uninstall 2.0). In v1.8, Road Graph exported my shortest path results to a shapefile just fine, which I was then able to use in 2.0.


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ESRI have a new tool that allow to add GTFS to a Network Dataset, display GTFS Route Shapes, edit GTFS Stop Locations, calculates transit/walking service areas for a specific time of day and day of the week, and more effective gadegets. There is also a blog avout this tool with samples to each procedure a lot of more links


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thank you for choosing OSM to realize that project :) Sadly our strength is creating a map and communication/docs is still WIP. Please understand, that OSM is a geodatabase and thus it can be used in very different ways to create services and offer this data offline. I say this to make clear e.g. that there is an API, but that isn't tuned for your specific ...



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