Hi All, The following question is only for test and comparison reason. Is there a command line option to set up using 1-Norm(sum of absolute value of residuals) as convergence monitor and test.
Alternatively, if I can get the residual "r" out at the end of each iteration, then it is going to be much simpler, since I can just call VecNorm(r, NORM_1, &r_ell1) and pass the r_ell1 into the convergence monitor and test. Can anyone inform me if PETSc has an interface for the resuidual r? Or one has to call the convergence test: MyKSPConverged(ksp,n,rnorm,flag,dummy); and following the steps: 1. fetch the exact solution: KSPBuildSolution(ksp,PETSC_NULL_OBJECT,x,ierr) 2. calculate the residual: pass the Right Hand side and the Matrix in to calculate the 1-Norm. But this step is *not* obvious, since the matrix and rhs is already distributed over each processes. 3. set up the convergence test based on the 1_Norm residual. Thank you very much, Yan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20090921/23595443/attachment.htm>
