Hong, On 07.02.2012 17:06, Hong Zhang wrote: > Alexander: > Thanks for sending matrix data and testing code. > Before testing it, I have question about your code: > > > MatCreateMPIAIJ(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, N, > M, 12, PETSC_NULL, 12, PETSC_NULL, &AT); > > MatTranspose(A,MAT_IGNORE_MATRIX,&AT); > > > should be replaced with > MatTranspose(A,MAT_INITIAL_MATRIX,&AT);
Hm, it seems this was the reason... > > To compare results I use following Matlab script: > > Cm = A.'*B; > > ^ > > Do you mean 'Cm = A'*B;'? > 'Cm = A.'*B;' gives component-wise matrix product, not matrix product. .' operator means non-Hermitian transpose. That is what I get with MatTranspose (in contrast with MatHermitianTranspose) component-wise matrix product would be .* > > Hong > > C = PetscBinaryRead('C.dat','complex',true); > > Matrix C is different depending on number of cores I use. > My PETSc is: > Using Petsc Development HG revision: > 876c894d95f4fa6561d0a91310ca914592527960 HG Date: Tue Jan 10 > 19:27:14 2012 +0100 > > > On 06.02.2012 17:13, Hong Zhang wrote: >> MatMatMult() in petsc is not well-tested for complex - could be >> buggy. >> Can you send us the matrices A and B in petsc binary format for >> investigation? >> >> Hong >> >> On Mon, Feb 6, 2012 at 5:55 AM, Alexander Grayver >> <agrayver at gfz-potsdam.de <mailto:agrayver at gfz-potsdam.de>> wrote: >> >> Dear PETSc team, >> >> I try to use: >> call >> >> MatMatMult(A,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT_DOUBLE_PRECISION,C,ierr);CHKERRQ(ierr) >> >> Where both A and B are rectangular, but A is sparse and B is >> dense. Both are double complex and distributed. >> The product PETSc gives me contains some errors in some part >> of the matrix. >> I output A, B and C then computed product in matlab. >> >> Attached you see figure plotted as: >> imagesc(log10(abs(C-Cm))) >> >> Where Cm -- product computed in matlab. >> >> The pattern and amplitude vary depending on the number of >> cores I use. This picture is obtained for 48 cores (I've >> tried 12, 64 cores as well). >> >> Where should I look for possible explanation? >> >> -- >> Regards, >> Alexander >> >> > > > -- > Regards, > Alexander > > -- Regards, Alexander -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20120207/6be117df/attachment.html>