Custom / Composite Matrix Assembly

Discussion about coding and new developments
Post Reply
josie
Posts: 3
Joined: 31 Jan 2020, 16:18
Antispam: Yes

Custom / Composite Matrix Assembly

Post by josie »

Hi!
I'm a bit stuck on a programming task. I would like to solve a system Ax=b using Elmer, where A = B+C*D, where B and C can be assembled as finite element matrices, but D is a dense matrix.
It is not really a problem to write routines to assemble each of the individual matrices, but I am stuck on fitting it into the existing Elmer structure. My main questions are:
  • Is something like this possible with the usual Elmer linear solvers? My concern is the matrix A would be dense and possibly have a bad condition number.
  • How could I allocate and access additional FE matrices (i.e. B and C) to assemble them with FE routines?
  • How could I do the final step of accessing all three assembled matrices to compute the total matrix A?
I would be very thankful for any help or ideas!
Post Reply