On Fri, Feb 8, 2013 at 4:48 PM, Rashad M <[email protected]> wrote: > > Hi, > > On Thu, Feb 7, 2013 at 2:46 PM, Moritz Lennert > <[email protected]> wrote: >> >> On 07/02/13 06:31, Rashad M wrote: >>> >>> Hi >>> >>> As mentioned in wiki does the output pixel = eigenvector * input pixel? >> >> >> Yes, possibly depending on how the eigenvector is formulated. PCA is >> "just" a linear transformation from original pixel space to PC space. > > > What do you mean by depending on "how the eigenvector is formulated"?
>From the example in the manual: The first PCA has the eigenvector 0.2824, 0.3342, 0.5092,-0.0087, 0.5264, 0.5217 Thus the output cells for PCA1 are calculated with PCA1 = 0.2824 * (band1 - mean(band1) + 0.3342 * (band2 - mean(band2) + ... + 0.5217 * (band7 - mean(band7)) The output cells for the other PCA's are calculated accordingly. > > Can anyone confirm this because its blocking me HTH, Markus M _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
