Hi devs!
I am using i.pca again and I've noticed some differences in the resulting numbers (eigen-values, vectors and importance). After browsing the source code, I found that there was a bug-fix 3 months ago [1]. This explains some previous disagreement between grass' i.pca and R's function(s) prcomp (for example). That's good news, Thanks :-) However, I am still troubled as to why R's prcomp() function gives different results than it did some months before. I run the scripts I used before on the same unchanged data and prcomp() gives completely different numbers. I could not find any significant code-change(s), while searching the respective changelog(s), for prcomp() nor for spgrass6. I don't want to trouble you with my problems but I am forced to ask: was there recently any _very_ important change in the raster engine (grass64, grass65), the region settings perhaps, or the way grass-rasters are imported in R via spgrass6 in the last months? Apologies for cross-posting, Nikos --- [1] http://trac.osgeo.org/grass/changeset/39800/grass/branches/develbranch_6/imagery/i.pca/main.c _______________________________________________ grass-stats mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-stats
