Dear all,
some degrees of freedom of my solution vector are constrained. When solsing the linear system A*x=b, I use the first approach as described in "Constraints on degrees of freedom". That is, I call constraints.distribute_local_to_global(...,false) and, after solving the linear system, constraints.distribute(...). My question pertains to the following: Say, I have in total 20 dofs and the dof with global dof index Zero is constrained. As a consequence, the first component of the rhs b is set to Zero as well as the first row and column of the system matrix A (except the diagonal value). In a postprecessing step, I have to solve another linear system, however, with the system matrix being only the 19x19 matrix associated with the 19 unconstrained dofs; I do not need the rhs anymore. Is there a way to get this portion of the system matrix based on the existing system matrix (sparsity pattern)? Thank you, Simon -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/219e5a2e-06f3-400e-a3db-6e022020587an%40googlegroups.com.
