From your code it looks like you are accessing values in a single row, changing them and then putting them back in the same row at the same index locations?
If this is the case you should use MatGetRow() to process the values, change the numerical entries in that row as needed and then call MatRestoreRow(). No need to call MatSetValues() and hence no business about unassembled matrices. Will this work for you? Barry > On Jan 28, 2018, at 2:16 PM, Ali Berk Kahraman <[email protected]> > wrote: > > Dear Barry, > > I see what you are talking about, I have oversimplified my problem. The > problem is that I will have to call MatGetValues on Wavelets matrix for every > row in a loop. Thus, if I do not call assembly routine in the child function, > it starts to give "not for unassembled matrix" error after the first loop. > The relevant part of the code is appended on this e-mail. You can see the > matgetvalues calls on line 81, and it is also in line 94's function > GetWaveletPolyFit2DSingleRow_x1. > > > Ali > > > On 28-01-2018 22:24, Smith, Barry F. wrote: >> In your code there is NO reason to call the MatAssemblyBegin/End where you >> do. Just pull it out and call it once. I submit this is the same for any >> other code. Please explain enough about your code (or send it) that has to >> call the assembly routines a different number of times. You just pull it >> above all the calls to MatSetValues(). >> >> Barry >> >> >>> On Jan 28, 2018, at 1:15 PM, Ali Berk Kahraman <[email protected]> >>> wrote: >>> >>> Hello All, >>> >>> >>> My apologies, I have closed this e-mail window and the first thing I read >>> on the manual is "ALL processes that share a matrix MUST call >>> MatAssemblyBegin() and MatAssemblyEnd() the SAME NUMBER of times". So I >>> understand that petsc simply does not support unequal number of assembly >>> calls. >>> >>> >>> My question evolves then. I have a problem at hand where I do not know how >>> many calls each process will make to MatAssembly routines. Any suggestions >>> to make this work? >>> >>> On 28-01-2018 22:09, Ali Berk Kahraman wrote: >>>> Hello All, >>>> >>>> >>>> The code takes a parallel matrix and calls a function using that matrix. >>>> That function fills the specified row of that matrix with the id of the >>>> process that part of the matrix belongs in. You can see the short code in >>>> the attachment, it is about 80 lines. >>>> >>>> >>>> The problem is that the code gets into a deadlock at some point, usually >>>> at the last row of each process except for the last process (greatest >>>> pid). I use petsc with configure options "--with-cc=gcc --with-cxx=g++ >>>> --with-fc=gfortran --download-mpich --download-fblaslapack". >>>> >>>> >>>> I am a beginner with MPI, so I do not know what may be causing this. My >>>> apologies in advance if this is a very trivial problem. >>>> >>>> >>>> Best Regards to All, >>>> >>>> >>>> Ali Berk Kahraman >>>> >>>> M.Sc. Student, Mechanical Eng. >>>> >>>> Bogazici Uni., Istanbul, Turkey >>>> > > <PetscRealProblem.c>
