Hello, this is a continuous question of this post:

I’m wondering that is it possible to create the sparse pattern for a function space using the current functions in DOLFINX, I can see that the MPC library has seperate functions for the sparse pattern.

Or, can I do something when I assemble the matrix, such that I can break the sparse pattern to get the mass matrix, assuming my dofmap is correct. (Sorry I’m not familer with PETsc stuff, so this question maybe a little bit naive).