Hello! Thanks Matthew Knepley and Barry Smith for the answers to my previous questions!
I am solving Ax = b with PETSC BiCGStab with user-defined preconditioner and want to compare it with other iteration process. The question is 1) Is there a possibility to monitor a user-defined function of residual norm(e.g., useer-defined computation of NORM_1) at each iteration of PETSC solver? (I cannot rewrite the user-defined routine for residual norm using PETSC interface since it is just fixed and given to me)? ------ It seems now that the residual norm (L1 = NORM_1) is calculated somewhat different through PETSC and user-defined routine. The difference is rather small but still for comparison with other solver I would prefer to have the same numbers. As a result, by now I have different values of residual norms measured for the same data by PETSC and external user-defined routine. (I checked it just be getting arrays from PETSC vectors and then giving them to the user-defined routine of residual norm). I found KSPSetConvergenceTest but the convergence is measured always in terms of NORM_2 of the error as far as I understand. Thanks in advance! -- Best regards, Kirill Voronin
