Hi,
using the keyboard shortcuts you need to select the entire variable, then you can insert the 3rd index...
f.e. type: variableName [ 2 [ 3 -> [
to create the reference for the nested matrix ("->" is the right arrow)
[MATH lang=eng]el(el(variableName,2,3),#)[/MATH]
using function names you need to write: el(el(variableName,2,3),1)
regards,
w3b5urf3r

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