# Commutation of the partial derivatives on scalar in xAct

I do not know how to automatically commute partial derivatives on a scalar and simplify it. For example, if I have: $$\partial_a \partial_b \partial_c f- \partial_c \partial_a \partial_b f$$ where $$f$$ is a scalar function, the ToCanonical and Simplification command do not simplify this. I also use CommuteCovdsonScalar command, but it doesn't work as well. Could anybody help me?