Access to tensor components


What i want to do seems to be pretty simple, but i can’t find a way to do it…

Let’s say i have a 2x2rank tensor A.
I want to compute simple operations like:
with a and b scalar like variables.
Using brackets to access tensor components seems to be correct according to the doc (, page 32) but the solver diverged. When i try to debug the code to find the problem, it seems that all variables defined with a operation based on tensor component are problematics.

Is the use of tensor components is correct ?


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