python - Sympy: Drop terms without a specific variable

Question

I'm trying to compute some (a lot) of multivariate conditional densities (i.e., the multiplication of several multivariate probability density functions). I'm able to set up and expand the matrices properly but now would like to drop terms that, for example in the equation below, don't contain . I thought the match method of the expanded object would be the way to go, but this returns None (or everything if I try the Wild method).

Thanks!

Answer 1

等待大神解答