[GRASS-user] Error while running i.gensig- Signature 1 not positive definite

[Kim Besson]

Greetings

I have a training area map and a few landsaty images, and everytime i try to
generate a signature I get this error/warning:
Signature 1 not positive definite

What might be causing this? can this be a problem of my dataset? (must it
range in some interval of values or what is wrong with it)?
How can I avoid this?
And what does it mean Not positive definite?
Thanks
Kim Besson
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