Ghosh: > > > Thanks for the suggestion of Elemental. However I need to have the > dense matrix have the same parallel communicator as the sparse matrix. > If I use elemental, then the numbering changes, will I be able to multiply > with the sparse matrix which has a different numbering scheme and > communicator? > > In any case I would want the resultant matrices A and M to be elemental > type since I need to solve a dense eigenvalue problem. >
If your final goal is solving a dense eigenvalue problem, and the only sparse matrix is a banded matrix H, Elemental is a suitable package. I just added HermitianGenDefiniteEig() into petsc(master)-elemental(v0.84) interface and tested on some large matrices - seems quite efficient. You may take a look at ~petsc(master)/src/mat/examples/tests/ex174.cxx I'm not sure if the latest Elemental supports banded dense matrix - if not, ask Jack to added :-) Hong > > ------------------------------ > *From: *"Hong" <[email protected]> > *To: *"Swarnava Ghosh" <[email protected]> > *Cc: *"PETSc users list" <[email protected]> > *Sent: *Thursday, February 5, 2015 8:22:13 PM > *Subject: *Re: [petsc-users] Large rectangular Dense Transpose > multiplication with sparse > > > Swarnava: > The matrix product A will be a dense matrix. You may consider using > Elemental package for such matrix product. > > Hong > >> >> Dear all, >> >> I am trying to compute matrices A = transpose(R)*H*R and M = >> transpose(R)*R where >> H is a sparse (banded) matrix in MATMPIAIJ format (5 million x 5 >> million total size) >> R is a MPI dense matrix of size 5 million x 2000. >> >> I tried 1) MatPtAP - Failed, realized this only works for pairs of AIJ >> matrices >> 2) First multiplying H*R and storing in 5 million x 2000 MPI >> dense. Then MatTranspose of R and multiplying the transposed R with 5 >> million x 2000 dense. This multiplication fails. >> >> Could someone please suggest a way of doing this. >> >> Regards, >> Swarnava >> -- >> Swarnava Ghosh >> > > > > > -- > Swarnava Ghosh > PhD Candidate, > Structural Engineering, Mechanics and Materials > School of Civil and Environmental Engineering > Georgia Institute of Technology > Atlanta, GA 30332 >
