Also, make sure you mask any Nulls since that often seems to be the problem when i.cluster doesn't work as expected, especially if you are using landsat 7 slc-off imagery - although I've also experienced it with Landsat 4 and 5 imagery.
[Sent from a mobile device] On Feb 18, 2011, at 4:38 PM, Nick Jachowski <njachow...@gmail.com> wrote: > Hi Ned and Daniel, > > I have run into this problem in the past, and I believe it may have to do > with your convergence, min_size, and classes settings. Try decreasing some > of those and see if you don't get better results. You can also try > increasing your separation from 0.0 (the default) to 1.0 or 1.5. > > Nick > > On Fri, Feb 18, 2011 at 4:24 PM, daniel mcinerney > <daniel.o.mciner...@gmail.com> wrote: > Hi Ned, > > I have been using i.cluster in GRASS 7 on a 64-bit fedora server, > without any trouble. However, I managed to replicate your problem > and create a single class output by setting the parameter > 'sample=5,5' as you had done in your example. If I run i.cluster without > that parameter, the signature file and classification output both > have the number of predefined classes. > > Can you see if this helps with your data? > > Regards, > Daniel. > > > On Thu, Feb 17, 2011 at 7:49 PM, Ned Horning <horn...@amnh.org> wrote: > Hi - I would like to do an unsupervised classification using i.cluster from > GRASS 7 on my Ubuntu 64-bit machine. When I run i.cluster then i.maxlik on a > Landsat image I only get one output class, the entire image. Only one class > appears in the signature file so the problem is with the i.cluster step. I > tried running i.cluster on different images and always get just one class. > > Here is the command line I'm using: > i.cluster group=TM_r15c33@PERMANENT subgroup=AllBands > signaturefile=IsoDataSigs2 classes=20 sample=5,5 convergence=99.9 > min_size=10000 > > Is anyone able to get i.cluster to work properly? It would be helpful to know > if it's a user problem or a bug. > > Thanks in advance to anyone who can help. > > All the best, > > Ned > _______________________________________________ > grass-user mailing list > grass-user@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-user > > > _______________________________________________ > grass-user mailing list > grass-user@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-user > >
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