Hong,
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. Regards, Swarnava ----- Original Message ----- 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
