I need to preform some sparse matrix-matrix calculations, but I only need a few of the non-zeros. Specifically, for A*B=C I only need the resulting C nonzeros where A has nonzeros. Forming all of C and then dropping the values I don’t need is prohibitively memory expensive.

It is my understanding that Julia makes use of cholmod_ssmult for this computation. What I’m asking is not implemented in cholmod_ssmult as far as I can tell. Are there any other libraries that can accomplish this? Is there a Julia way to accomplish this?