FMB - NLA
Block-tridiagonal matrices
. – p.1/31 FMB - NLA
Block-tridiagonal matrices - where do these arise?
- as a result of a particular mesh-point ordering
- as a part of a factorization procedure, for example when we compute the eigenvalues of a matrix.
. – p.2/31 FMB - NLA Block-tridiagonal matrices
Ω1 Ω2 Ω3 Consider a two-dimensional domain partitioned in strips. Assume that points on the lines of intersection are only coupled to their nearest neighbors in the underlying mesh (and we do not have periodic boundary conditions). Hence, there is no coupling between subdomains except through the “glue” on the interfaces.
. – p.3/31 FMB - NLA Block-tridiagonal matrices
When the subdomains are ordered lexicographically from left to right, a
domain Ωi becomes coupled only to its pre- and postdecessors Ωi 1
and Ωi +1, respectively and the corresponding matrix takes the form of