How to express log ?

[LiuPengPeter]

Hello everyone,
I have a small question.
In the expression pf my material energy, there is log.

How to write it?

[dschwen]

Are you asking about log in C++ (that'd be std::log(_u[_qp]) or whatever c is), or parsed materials (which would be log(c))?

[dschwen]

or rather

((1.0 - _u[_qp]) * std::log(1.0 - _u[_qp]) + _u[_qp] * std::log(_u[_qp]))```

and

((1 - c)  * log(1 - c) + c * log(c))

[LiuPengPeter]

You are so kind! Thank you.