Hi all, unfortunately, v.kernel seems to be in the GRASS modules blacklist, so it's not accessible from SEXTANTE now. Maybe, in the future? We talked about KDE in this thread in the past: https://lists.forge.osor.eu/pipermail/sextante-users/2009-November/000124.html There are other useful informations here: http://en.wikipedia.org/wiki/Kernel_%28statistics%29 such as the commonly used kernel functions: http://en.wikipedia.org/wiki/Kernel_%28statistics%29#Kernel_functions_in_common_use I think it's not hard to implement other kernel functions into the "Density (kernel)" tool. I'm quite busy at the moment, otherwise I would try to do it.
Cheers, Antonio Il 28/06/2011 11.13, G. Allegri ha scritto: > Through Sextante you can use GRASS, which implements you many more kernels: > http://grass.meteo.uni.wroc.pl/grass65/manuals/html65_user/v.kernel.html > > giovanni > > 2011/6/28 Benjamin Ducke > > Hi Joachim, > > The tool computes a Kernel Density Estimate (KDE), > which is a continuous estimation of a probability > function for all cells in your dataset. > > SEXTANTE's implementation uses a Gaussian kernel. > Other kernel types are not currently implemented. > > More details here: > > http://en.wikipedia.org/wiki/Kernel_density_estimation > > Best, > > Ben > > ----- Original Message ----- > > Dear sextante experts, > > > > we are using the Density tool with the "kernel". No technical > > problems, but three practical questions: > > > > - we are looking for the data output of the function. Where is it ? > > How can we get it ? > > - the result of the kernel function is definitely good looking. > But we > > can't explain it. What does the gradient represent ? Is it a real > > gaussian standard distribution, or what ? > > - how would we proceed to obtain a similar output, but with a linear > > gradient or a gravitational (1/d^2) gradient ? > > > > Many thanks, > > > > Joachim > > _______________________________________________ Sextante-users > mailing > > list Sextante-users@lists.forge.osor.eu > <mailto:Sextante-users@lists.forge.osor.eu> > > https://lists.forge.osor.eu/listinfo/sextante-users > > > ------ > Files attached to this email may be in ISO 26300 format (OASIS Open > Document Format). If you have difficulty opening them, please visit > http://iso26300.info for more information. > > _______________________________________________ > Sextante-users mailing list > Sextante-users@lists.forge.osor.eu > <mailto:Sextante-users@lists.forge.osor.eu> > https://lists.forge.osor.eu/listinfo/sextante-users > > > > > _______________________________________________ > Sextante-users mailing list > Sextante-users@lists.forge.osor.eu > https://lists.forge.osor.eu/listinfo/sextante-users -- Antonio Falciano http://www.linkedin.com/in/antoniofalciano _______________________________________________ Sextante-users mailing list Sextante-users@lists.forge.osor.eu https://lists.forge.osor.eu/listinfo/sextante-users
