Re: [deal.II] PETSC SparsMatrix initialization error

[Zachary 42!]

No, that's not what you want. You need to partition the columns in the same way as you partition the vectors you want to multiply the matrix by. We generally partition the vectors in the same way as the rows of the matrix, and so then you also have to choose the same partitioning for the columns of the matrix. Ah okay, I thought I wasn’t explaining my desired layout well.  I will change my matrix layout so I can have distributed square sparse matrices. If you look at the backtrace, at which point do you get this error? Is it really out of the SLEPC functions? I would suspect that it comes out of the set-up phase for your matrix. Yes, the error comes when I try to use the Slepc solver (the matrix builds without errors).  Running the attached file (Sorry, I’v been experimenting trying to get things working so I think I should include what I am testing now), At the bottom of the error output, I get: ---------------------------------------------------------------------------------------------------------------------------------------------------- An error occurred in Line <169> of file </Users/zachary/Documents/dealii/source/lac/slepc_solver.cc> in function void dealii::SLEPcWrappers::SolverBase::solve(const unsigned int, unsigned int*) The violated condition was: ierr == 0 Additional information: An error with error number 60 occurred while calling a SLEPc function ------------------------------------------------------------------------------------------------------------------------------------------------------ -Zachary -- 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/93297721-D794-49CE-BCAC-52080F39C661%40gmail.com.

step-test_reinit.cc
Description: Binary data

On Jan 8, 2021, at 2:13 PM, Wolfgang Bangerth <bange...@colostate.edu> wrote: You said “the local number of columns also needs to add up to the global number of columns” but my desired layout is local_num_columns == global_num_columns. No, that's not what you want. You need to partition the columns in the same way as you partition the vectors you want to multiply the matrix by. We generally partition the vectors in the same way as the rows of the matrix, and so then you also have to choose the same partitioning for the columns of the matrix. I only press this because I get the similar dimension error when I tried to use Slepc to solve the test matrix so maybe my initial sparse matrix dimension is wrong (or my matrix).  Please take a look at the file I am attaching.  It’s the same code you ran before but I added a section using Slepc to solve the eigenvalue problem.  It’s bare bones and produces the dimension error just like before.  This code works for one processor and given the error, this is not a surprise.  For 2 processors, I get “Sum of local length 64 does not equal global length 128, my local length 64”. If you look at the backtrace, at which point do you get this error? Is it really out of the SLEPC functions? I would suspect that it comes out of the set-up phase for your matrix. 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 a topic in the Google Groups "deal.II User Group" group. To unsubscribe from this topic, visit https://groups.google.com/d/topic/dealii/If0Ep9rJ67Q/unsubscribe. To unsubscribe from this group and all its topics, send an email to dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/8741cd0a-8f48-8c67-ae10-1c5c6a3d7802%40colostate.edu. -- 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/93297721-D794-49CE-BCAC-52080F39C661%40gmail.com.