Chris,
In addition to the resolution issue noted below, I discovered another undocumented limitation to i.cluster or i.maxlik that was causing it not to classify my ASTER data (I don't know in which it is). Apparently, one or both of the programs will not handle more than 7 bands (actually I haven't yet tested 8, but know they won't handle 9). I suppose that when they were written this was a compromise for the available processing power of normal computers and the kinds of imagery readily available. Now, with more processing power and imagery with more bands, I wonder it this limitation could be raised?
Michael
____________________
C. Michael Barton, Professor
School of Human Origins, Cultures, & Societies
PO Box 872402
Arizona State University
Tempe, AZ 85287-2402
USA
Phone: 480-965-6262
Fax: 480-965-7671
www: <www.public.asu.edu/~cmbarton>
On May 6, 2004, at 5:11 PM, Chris G. Nicholas wrote:
cool...glad there aren't any fundamental problems here...
did you ever get i.clust to run, and if so, how were the results?
Chris
-----Original Message-----
From: Michael Barton [mailto:michael.barton@asu.edu]
Sent: Thu 5/6/2004 3:07 PM
To: Chris G. Nicholas
Cc: GRASS5 list; GRASSLIST@baylor.edu
Subject: Re: [GRASS5] image analysis question - FORGOT IMPORTANT INFORMATION
Chris,I figured out what is going on...I think. ASTER comes in 3 resolutions:
3 15m vnir bands, 6 30m swir bands, and 5 90m tir bands. Because GRASS
will dynamically adjust resolution on the fly, depending on the region
setting, I can view any combination of bands at any of these
resolutions. However, if I want to run i.clust, all the bands I use
need to be at the same resolution. Hence, I need to change the
resolution using r.resample to make sure that all the bands I am
clustering match. The reason it works without a problem with Landsat is
that all bands (except band 8 for ETM) are the same 28.5m resolution.Michael
______________________________
Michael Barton, Professor & Curator
School of Human Origins, Cultures, & Societies
Arizona State University
Tempe, AZ 85287-2402
USAvoice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton
On Apr 28, 2004, at 1:00 PM, Chris G. Nicholas wrote:hmmm...not sure about ASTER...but I know that things seem to work on
Landsat images.Chris
-----Original Message-----
From: Michael Barton [mailto:michael.barton@asu.edu]
Sent: Tue 4/27/2004 8:41 AM
To: GRASS5 list
Cc:
Subject: [GRASS5] image analysis question - FORGOT IMPORTANT
INFORMATION
I got interrupted by some student questions while finishing my query
about problems in using i.cluster, i.maxlik, and i.smapI forgot to mention that I am using GRASS 5.3 (early April build) on a
Mac OSX 2.8 platform.Michael
______________________________
Michael Barton, Professor & Curator
Department of Anthropology
Arizona State University
Tempe, AZ 85287-2402
USAvoice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton