On Sun, Nov 16, 2014 at 3:21 AM, Vaclav Petras <[email protected]> wrote: > Hi, > > I executed the examples in i.cluster and i.maxlik manuals and also the > following i.segment command: > > i.segment group=lsat7_2002@w1-imagery output=lsat7_2002_segments > threshold=0.5 goodness=lsat7_2002_segments_goodness > > (using the imagery group created in i.cluster example, otherwise unrelated) > > I looked at goodness from i.segment and then reject from i.maxlik. I noticed > that there is some correlation between these two. Well, this is quite okay > since they are using same pixel values. However, then I noticed that low > values of goodness (-5000, ...) correlate with low values of reject (1 == > 1%). But the i.maxlik manual says that "1 = keep and 16 = reject". Can > somebody explain this to me and perhaps suggest improvement to the manual? > Shouldn't high rejection correlate with low goodness?
Unless someone looks at the source code, the i.maxlik manual may simply be wrong. A nice, synthetic test case would be the best. > And also, less important thing, i.maxlik reject is an categorical map with > percentages reclassified to 16 classes. Does this have some practical > meaning or is this just an over-left from integer-only times? Yes, that's likely and should be changed. Markus > Thanks, > Vaclav > > http://grass.osgeo.org/grass71/manuals/i.cluster.html > http://grass.osgeo.org/grass71/manuals/i.maxlik.html > http://grass.osgeo.org/grass71/manuals/i.segment.html > > _______________________________________________ > grass-user mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/grass-user _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
