Hi everybody!

How can I specify an index in an expression to pintegrate act on?

For example, I want to do an integral by part on

\partial_{a}{F} \partial_{b}^{a b}{G}

to form

\partial_{a}^{a}{F} \partial_{b}^{b}{G}

'integral by part' can not deal with the multiple index by now. you can run the following in cadabra:

\partial{#}::PartialDerivative; ex:= \int{ \partial_{b}{ \partial^{a}{\partial^{b}{A}} } B C D}; integrate_by_parts(_, $A$);