Thanks, Prof. Bangerth, this really helped. Regards Vinayak
On Wednesday, February 14, 2024 at 5:17:08 AM UTC+5:30 Wolfgang Bangerth wrote: > On 2/13/24 10:53, Vinayak Vijay wrote: > > > > The error says "You are trying to access the matrix entry with index > <54,0>". > > *This seems to be inconsistent with the constraint matrix* (printed in > the > > output above)*. *I am also attaching the sparsity pattern if needed. > > > > Can someone help me with this? Also, since this procedure of applying > > constraints in the solver routine is quite different from the usual, it > would > > help if someone could confirm that the above way of applying constraints > is > > correct and/or if there's anything else i need to keep in mind. > > If you have an entry such as <54,60> and a constraint that ties DoF 60 to > DoF > 0, you will end up writing into entry <54,0>. > > In the end, you need to ensure that when you build the sparsity pattern, > you > introduce all entries you will write to. You don't show how you build the > sparsity pattern, but suspect that you call > DoFTools::make_sparsity_pattern(). > When you do this, you need to provide an AffineConstraints object that > includes all constraints, or you will get errors just like the ones you > see. > > Best > W> > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > www: http://www.math.colostate.edu/~bangerth/ > > > -- 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/85507385-71cf-4306-826d-6b194c5405d7n%40googlegroups.com.
