> On Feb 3, 2019, at 1:16 PM, Edoardo alinovi <edoardo.alin...@gmail.com> wrote: > > Thank you very much Barry for the suggestion. > > Unfortunately, I am using Fortran and not C++ . Do you have an equivalent > trick in this case? :) You would need to provide this function as a C function (in its own little .c file) and then call it from your Fortran code. Barry There is no way to access the data structure directly from Fortran. > ------ > > Edoardo Alinovi, Ph.D. > > DICCA, Scuola Politecnica, > Universita' degli Studi di Genova, > 1, via Montallegro, > 16145 Genova, Italy > > Email: edoardo.alin...@dicca.unige.it > Tel: +39 010 353 2540 > > > > > > Il giorno dom 3 feb 2019 alle ore 20:03 Smith, Barry F. <bsm...@mcs.anl.gov> > ha scritto: > > If you use the default KSP convergence tests (which almost everyone does) > the initial residual norm is stored in ksp->rnorm0. Thus to access it you > need to include the private header file that defines the KSP object kspimpl.h > so something like > > #include <petsc/private/kspimpl.h> > > PetscErrorCode KSPGetInitialResidualNorm(KSP ksp,PetscReal *norm0) > { > *norm0 = ksp->rnorm0; > return 0; > } > > should work. > > Barry > > > > > > > > On Feb 3, 2019, at 8:27 AM, Edoardo alinovi via petsc-users > > <petsc-users@mcs.anl.gov> wrote: > > > > Dear all, > > > > I have a very simple question for you. How can I get the initial residual > > from a ksp solver? I can easily extract the final (preconditioned) residual > > norm but when I try to use to do the same with the initial residual using: > > > > kspInitialResidual() > > > > PETSc tells me that this feature is not supported. I am actually doing it > > applying the definition of residual "by hand", but I am wondering if > > somenthing already built-in is available or not. > > > > Thank you very much! > > ------ > > > > Edoardo Alinovi, Ph.D. > > > > DICCA, Scuola Politecnica, > > Universita' degli Studi di Genova, > > 1, via Montallegro, > > 16145 Genova, Italy > > > > Email: edoardo.alin...@dicca.unige.it > > Tel: +39 010 353 2540 > > > > > > >
Re: [petsc-users] Ksp Initial residual norm
Smith, Barry F. via petsc-users Sun, 03 Feb 2019 11:26:25 -0800
- Re: [petsc-users] Ksp Initial residual nor... Smith, Barry F. via petsc-users
- Re: [petsc-users] Ksp Initial residua... Smith, Barry F. via petsc-users
- Re: [petsc-users] Ksp Initial res... Matthew Knepley via petsc-users
- Re: [petsc-users] Ksp Initial... Smith, Barry F. via petsc-users