Dear All, I am trying it through PETScWrappers::MPI::Block data type.
=============================================================== SolverControl solver_control1 (rVec.block(0).size(),1e-8*rVec.block(0).l2_norm()); PETScWrappers::SolverCG cg1 (solver_control1,mpi_communicator); PETScWrappers::PreconditionSSOR pre1 (system_matrix.block(0,0)); cg1.solve (system_matrix.block(0,0) , dVec.block(0) , dum , pre1); =============================================================== When it runs, below error are occurred. ---------------------------------------------------- Exception on processing: Iterative method reported convergence failure in step 1 with residual 31.7698 Aborting! ---------------------------------------------------- But, I definitely set up the maximum number of iteration for CG by a rVec.block(0).size(). CG solver for PETScWrappers::MPI::Block just worked up to first step. What more nothing was understandable is that it works well if rVec.block(0) = 0, even though solution is zero vector , But, otherwise,(rVec.block(0) is not empty) it does not work. Where was wrong? _______________________________________________
