EM Unsupervised Classification Probability Expressions

Hello Everyone,

I would appreciate if someone can explain to me how the Edit Expression works with specific reference to the operators such as ‘@-@, @*@, and @/@’. I have gotten the ‘@+@’ expression to work perfectly, but i am having trouble with the others.

Thank you.

can you please bring an example? I don’t get how this is related to image classification.

When I ran the Em classification on Sentinel 2 Imagery it produced a total of 100 probability each possibility can be represented in a color gun (RGB).

Each probability can be projected in each color gun and projected. Each probability gives characteristics that can be used to identify or generate a feature based on the pixels in each probability displays.


These probabilities can then be combined to create a more holistic and precise projection of the desired feature(s) by adding several probabilities together in each color gun under edit expression, an entire feature can be projected in one color.

What I’m having issues with is that when i use the other operators I don’t get a proper result. As I’m doing this by trial and error i am attempting to figure out if i am making an error somewhere. I was unable to find any related topics concerning this specific issue. That’s why I’m asking here. I really hope i can get some assistance.

Even after your explanation I don’t see your problem with the expressions.
The operation you are referring to simply contain placeholders ‘@’ and multiplcator and subtractor etc.
If you can apply probability_17 + probability_30 you should be able to apply probability_17 / probability_30.
Why do you think the result is not ok when you use the other operators?
And why do think the addition works, what is the reference you compare with?

thanks for the explanation, now I get your point.
I haven’t tested it but I would also think that basic mathematical functions should work on these probabilities.