On Thu, Sep 19, 2013 at 8:30 PM, Jed Brown <[email protected]> wrote:
> Frank <[email protected]> writes: > > > Hi, > > > > I am thinking of solving a linear equations, whose coefficient matrix > > has 27 nonzero diagonal bands(diagonal dominant). Does any body have any > > idea about how this will perform? Do you have any recommendation about > > which solver to choose? > > How far away from the diagonal are those bands, as a function of the > grid size (if relevant)? > > http://scicomp.stackexchange.com/a/880/119 > http://scicomp.stackexchange.com/a/869/119 If your matrix/preconditioner has bandwidth K which is small and is diagonally dominant, you can solve it efficiently using http://en.wikipedia.org/wiki/SPIKE_algorithm. Thanks, Matt > > I have solved a 11 nonzero diagonal bands matrix equation with > > "boomeramg", which is 50% solwer than 7 nonzero diagonal bands. > > This doesn't mean much of anything. Send -log_summary if you have > performance questions. > > Why does the subject of this email say "dense"? > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
