Hi As mentioned in wiki does the output pixel = eigenvector * input pixel?
On Thu, Feb 7, 2013 at 10:59 AM, Rashad M <mohammedrasha...@gmail.com>wrote: > Thanks Nikos and Mortiz, > > From GRASS Wiki what I got is I need more details of step.6 in the > Background section > i.e *project original dataset signals* (PC's or PC scores: eigenvector * > input-data) to get > > projecting the dataset is based on the text output of i.pca eigen values > and input data. > > I guess there must be a simple transformation equation that can be applied > to every pixel in the input data to get the raster output of i.pca. > > Nikos, Your thesis is a long read and I only need a very small part from > it. If you could tell me those( I strongly believe you can ) then it will > be great. I need to start coding after this and this is only a small part > of it. my actual work is pure pixel identification for spectral unmixing > > > On Thu, Feb 7, 2013 at 5:43 AM, Nikos Alexandris > <n...@nikosalexandris.net>wrote: > >> Rashad M wrote: >> >> > > Hi All, >> >> > > i.pca outputs raster bands and the pixel values are transformed >> > > obivously. But anyone can tell me how the transformation works >> >> > > if a pixel P1 has value X after i.pca it will be Y >> >> > > Is there any specific math equation that is applied to every pixel by >> PCA? >> >> Moritz Lennert wrote: >> >> > http://en.wikipedia.org/wiki/Principal_component_analysis >> > and >> > http://grasswiki.osgeo.org/wiki/Principal_Component_Analysis >> >> Ehm, right -- I've overlooked your post Moritz, apologies. >> >> Nikos >> _______________________________________________ >> grass-dev mailing list >> grass-dev@lists.osgeo.org >> http://lists.osgeo.org/mailman/listinfo/grass-dev >> > > > > -- > Regards, > Rashad > -- Regards, Rashad
_______________________________________________ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
