You mean I should put MatDestroy before Matcreate? But is it different from that if I put destroy just after create in current timestep? Thanks again Daye
发自我的 iPhone > 在 2018年5月12日，下午10:00，Matthew Knepley <[email protected]> 写道： > >> On Sat, May 12, 2018 at 8:08 AM, 我 <[email protected]> wrote: >> >> Thanks for your reply! I'm confused about how to create a new matrix during >> the time step advancing. >> For better understand my problem, simple pseudo code (just contains the main >> functions) like this: > > It looks like MatDestroy should come before the next Create. > > Matt > >> ///////////////////////////////// >> KSP ksp; >> PC pc; >> KSPCreate; >> Mat A; >> for(int timestep=0; timestep<20; timestep++) >> { >> //for example >> if(timestep==2) >> { >> localsize change; >> } >> MatCreateMPIAIJWithArrays(PETSC_COMM_WORLD, localsize, localsize, m, m, >> istore, jstore, vstore, &A); >> KSPSolve; >> >> MatDestroy(&A); >> } >> ///////////////////////////// >> Thanks again! >> Daye >> >> >> >> >> At 2018-05-11 19:07:35, "Matthew Knepley" <[email protected]> wrote: >>> On Fri, May 11, 2018 at 4:23 AM, 我 <[email protected]> wrote: >>> Hello all, >>> I use the function MatCreateMPIAIJWithArrays to construct my matrix. But >>> the number of local rows m and local columns n may change during the >>> timestep advancing. When the local size changes, the error like "Petsc >>> error: cannot chang local size of Amat after use old sizes 10 10 new sizes >>> 11 11" will appear. Any suggestions about it ? >> >> If the parallel layout changes, you need to create a new matrix. >> >> Thanks, >> >> Matt >> >>> Thank you very much! >>> Daye >>> >>> >>> >>> >> >> >> >> -- >> What most experimenters take for granted before they begin their experiments >> is infinitely more interesting than any results to which their experiments >> lead. >> -- Norbert Wiener >> >> https://www.cse.buffalo.edu/~knepley/ >> >> >> >> > > > > -- > What most experimenters take for granted before they begin their experiments > is infinitely more interesting than any results to which their experiments > lead. > -- Norbert Wiener > > https://www.cse.buffalo.edu/~knepley/
