On Sunday 18 November 2007, Martin Landa wrote: > Hi, > > [Cc: grass-user ML] > > 2007/11/18, Kristian Förster <[EMAIL PROTECTED]>: > > Dear GRASS developers, > > > > I am using GRASS GIS for some hydrological applications. For some > > questions like flood prediction it is useful to estimate the travel time > > of surface water in a basin to the outlet. Therefor I've developed a > > raster program "r.traveltime" which calculates the travel time for each > > cell in a basin from outputs of r.watershed and r.fill.dir. There is > > much literature about this procedure available but there's a lag of > > available software (GRASS and even ArcGIS do not come with such > > functions). The personal need an the lag of available programs were the > > reason for me to develop a new program for GRASS GIS. I am not a > > programming expert, so the program is very simple and far away from > > being perfect. Maybe if you are interested in these kind of extensions > > you may list it on your add-on page. Further it could be useful for > > other users of hydrological applications. > > > > r.traveltime is available here: > > http://home.arcor.de/jesbergwetter/software.html >
Interesting project summary! It looks like the algorithm is using something like the D8 flow routing algorithm, based on the cardinal direction-looking artifacts in Fig 4. Do you have a paper or the like detailing the internals? Or am I going to have to look at the code :) ? Thanks for sending the link, a colleague of mine may be able to use this in his current research. Cheers, Dylan -- Dylan Beaudette Soil Resource Laboratory http://casoilresource.lawr.ucdavis.edu/ University of California at Davis 530.754.7341 _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user