OK, I see. I will do it, thank you! I will let you know if I get any result.
On Mon, Aug 17, 2020 at 7:06 PM Wolfgang Bangerth <bange...@colostate.edu> wrote: > On 8/17/20 6:01 PM, yuesu jin wrote: > > I did nothing to verify those properties. because the single thread > CG > > solver converged well. I used different preconditioners in parallel > version > > and single thread version. In the parallel version I used block Jacobi > and in > > the single thread version I used Jacobi. How can I check if the parallel > > blocked sparse matrix is/ isn't symmetrical and positive definite? > > Think of tests such as this: > * run on 1 processor, multiply a vector w of all 1s from the right, and > output > the resulting vector v=Aw on all processors > * run on >1 processors and repeat > Are the vectors the same for both cases? The matrix should be the same > regardless of partitioning, but is it? > > * repeat the same with Tvmult (multiplication from the left) > > You can probably come up with many similar tests that check properties of > the > matrix, comparing between the single-processor and multiple-processor > cases. > The point is that you may not know the exact answer, but you know that the > two > cases should result in the same output. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: bange...@colostate.edu > 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 dealii+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/dealii/1c573208-1579-e2c9-672d-f6463630eead%40colostate.edu > . > -- Yuesu Jin, Ph.D student, University of Houston, College of Natural Sciences and Mathematics, Department of Earth and Atmospheric Sciences, Houston, Texas 77204-5008 346-404-2062 -- 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 dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/CA%2B25a%3D%2B2a%3D_bGh620BWu2__SViuzefkQYNxGMz_q4UX8JA4iDw%40mail.gmail.com.