On Wed, Mar 30, 2011 at 6:28 PM, ndekoning <[email protected]> wrote: > Hello, > > I have been trying to do an unsupervised classification of my WorldView2 > satellite image. When I am using i.cluster I receive the following message: > "ERROR: Illegal value(s) of sample intervals (100,100)". > These are my settings: > > group= mul_utm17n@PERMANENT > subgroup= utm17_sub > signaturefile= utm17n_sig > classes= 11 > sample= 100,100 > iterations= 30 > convergence= 99.9 > separation= 0.0 > minimum pixels= 17
I think that the default "separation=0.0" is suboptimal. Try 0.5. Here also an older posting: On Fri, Feb 18, 2011 at 9:05 PM, Ned Horning <[email protected]> wrote: > . I did manage to get it to run after playing with > some of the variables. If I used the default values for "sample" and > "min_size" it worked. Unfortunately the default values are less than ideal. > I think the main problem is with the "sample" parameter. When I enter > "sample=5,5" I assume that every fifth pixel from every fifth line is being > sampled for use in calculating the cluster statistics. This is apparently > too many samples for i.cluster to handle. If I use "sample=100,100" the > program works as expected (more or less). I have a feeling that the sample > array is not able to handle a large number of samples. Please post your findings so that we can eventually optimize the default parameters. Markus _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
