Thanks a lot everyone. Don't need it for a project at the moment but looking around for a client.
On Fri, Jun 19, 2015 at 8:50 AM, Mark Wynter <[email protected]> wrote: > I'd also recommend igraph. > Description below describes how I'm using igraph (cut and paste from an > earlier private email conversation). > > I still use grass for some aspects of topology cleaning (eg messy OSM > data), but igraph thereafter. > > This is how I'm using igraph currently... > > I use igraph directly from postgis via pl/r wrappers. I use it mainly for >> least cost routing instead of pgrouting. Besides igraph being a very fast >> routing engine, it opens up possibilities to embed the inputs or outputs >> within other analytics processes or visualizations. >> >> I've written igraph postgis functions that take >> wkb_geoms and build an igraph directed network object. >> >> Other postgis custom functions then query the network and return >> -Node to node Shortest path >> -Node to multinode shortest paths >> -Mode - inward vs outward directed shortest paths >> - travel distance matrices >> -all of the above using R's parallel computing capabilities >> - anything else which canbe done in igraph or R, and returned to >> Postgresql/postgis. >> >> I then use the results to build polylines, isochrones and cost surfaces >> on the fly using the new KNN lateral query pattern in postgis. >> >> And when you create a Postgis materialized view that calls these igraph >> functions, we can present dynamic QGIS visualizations. So if you drag the >> location of a hospital in QGIS, you see the postgis isochrones or >> accessibility surface immediately update when you hit save. >> >> The other thing to bear in mind is that igraph also comes as a python >> library so you might be able to mash up the line graphs into a QGIS panel - >> and instead of calling igraph in postgis via pl/r, you call it via >> pl/Python. Arguably you don't need postgis if you can access the igraph >> Python lib directly from qgis. > > > My recommendation would be igraph (http://igraph.org/). > > Powerful, Open Source (https://github.com/igraph), well documented, and > comes with Python, and C++ and R interfaces. > > I used it in the r.connectivity.network addon for GRASS 6 and was quite > happy with it! > > > Cheers > > Stefan > > > _______________________________________________ > Qgis-developer mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/qgis-developer >
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