I am trying to do an unsupervised classification using GRASS GIS software. I have hyperspectral photo and now analyzing vegetation indices. Here is what I did:

  1. Created 2000+ raster photos with different combinations of bands
  2. Created raster of signatures for the same area using the same mask
  3. Used i.group command to make group of all rasters that I have
  4. Used i.cluster command - and here is my problem:

WARNING: quantization file [gndvi_g40_n75] in mapset [xxx] missing WARNING: Unable to open header file for raster map WARNING: Unable to open raster map ERROR: Unable to open raster map

What should I do to not have those errors? It looks like i.group did not create everything properly...

So I cannot use i.maxlik without i.cluster

  • I removed some rasters and finally my group was taken by i.cluster. But now other problem: WARNING: Signature 1 is not valid (singular) - ignored WARNING: Signature 2 is not valid (singular) - ignored – AngelaG May 1 '18 at 21:10
  • Which operating system do you use? Because there is a related limit of how many files can be opened at the same time – markusN May 5 '18 at 12:22
  • I am using Linux by connecting with the server and working there, but normally I have Windows (I am not sure if this is important). – AngelaG May 6 '18 at 20:57
  • According to (random link) stackoverflow.com/a/870224/452464 Windows cannot open more than 512 at the same time. Maybe nowadays even 2000 but a GRASS GIS raster map consists of more than one file which needs to be opened. I suggest to open a bug report with details at trac.osgeo.org/grass#BugTracking in order to see if we could add a workaround here. – markusN May 6 '18 at 21:14

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