Avoid calculating material properties need only for Jacobian

[dzheng26]

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Question

For one nonlinear iteration, the method computeProperties of the material classes is called at least 2 times, once for calculating the residual and once for calculating the Jacobian.

Some properties generated by computeProperties are actually for calculating Jacobian only, for example the pk1_jacobian in solid mechanics. When computeProperties is called for calculating the residual, the calculation for pk1_jacobian is not really needed. For complicate material model, the calculation for pk1_jacobian maybe relatively heavy and slows down the simulation.

So my question is:
Is there a way to know in computeProperies if it is used for calculating the residual or the jacobian, or both (for Executioner/residual_and_jacobian_together=1)? If it is known, user can skip the properties which are used for the Jacobian only when computeProperties is called not for calculation the Jacobian.

[GiudGiud]

Hello

Yes there is a way. You can check the problem with "currentlyComputingJacobian"

_fe_problem.currentlyComputingJacobian()

returns a boolean.

Guillaume

[dzheng26]

Thanks for the quick answer. I will try it.