args

[LiuPengPeter]

Hello guys,

The args is related with computeQpJacobian and computeQpOffDiagJacobian. Sometimes I could make sure which variable is needed. Could I write all of variables except the "variable" ?

[lindsayad]

I don't understand your question. Can you add some more context/information please?

[LiuPengPeter]

For example, my kernel is F*c.
If F is the function of eta1, c1, eta2 and c2, then the args= 'eta1 c1 eta2 c2'.
If F is the function of c1 and c2, then the args= 'c1 c2'.
Sometimes I forget to change, so I wonder if I could write all of them at first even if some won't be used.

[dschwen]

That's not recommended as it will result in a combinatorial explosion of material property derivatives being requested. Properly written objects that require an args parameter should warn you if you are missing important variables in that list.

[LiuPengPeter]

Thank you.
I understand now. With all of variables added, it won't lead wrong result but the workload of simulation will be very large.