On Wed, 28 Jul 2010 19:18:43 +0200, "=?utf-8?b?0J3QtdC80LDRmtCwINCY0LvQuNGb?= (Nemanja Ilic)" <nemanja.ilic.81 at gmail.com> wrote: > Hello, > > I did the LU factorization and then pulled out diagonal from the matrix, but > the code breaks. It breaks on the MatAssemblyEnd after the followin lines:
You really need to tell us how it breaks (send the whole error message), it's rare that we can tell you what is wrong from "it breaks". > // now populate matrix > ierr = MatAssemblyBegin(Ap, MAT_FINAL_ASSEMBLY); CHKERRQ(ierr); > ierr = MatAssemblyEnd(Ap, MAT_FINAL_ASSEMBLY); CHKERRQ(ierr); [...] > ierr = MatLUFactor(Ap, perm, iperm, &info);CHKERRQ(ierr); This is not the correct interface, you have to use MatGetFactor first, you don't call MatLUFactor on the matrix you just assembled. Read the user's manual and/or look at an example http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/src/mat/examples/tutorials/ex13.c.html Jed
