Error using BoomerAMG with eqns

[Barry Smith]

   You use KSPGetPC(ksp_uv,pc_uv,ierr) but call  
PCSetType(pc,'hypre',ierr)

this is why you should ALWAYS, always use implicit none

    Barry



On Jun 9, 2008, at 9:46 PM, Ben Tay wrote:

> Hi,
>
> I tried to use BoomerAMG as the preconditioner. When I use ./a.out - 
> pc_type hypre -pc_hypre_type boomeramg, I got
>
> KSP Object:
> type: richardson
>   Richardson: damping factor=1
> maximum iterations=10000, initial guess is zero
> tolerances:  relative=1e-05, absolute=1e-50, divergence=10000
> left preconditioning
> PC Object:
> type: hypre
>   HYPRE BoomerAMG preconditioning
>   HYPRE BoomerAMG: Cycle type V
>   HYPRE BoomerAMG: Maximum number of levels 25
>   HYPRE BoomerAMG: Maximum number of iterations PER hypre call 1
>   HYPRE BoomerAMG: Convergence tolerance PER hypre call 0
>   HYPRE BoomerAMG: Threshold for strong coupling 0.25
>   HYPRE BoomerAMG: Interpolation truncation factor 0
>   HYPRE BoomerAMG: Interpolation: max elements per row 0
>   HYPRE BoomerAMG: Number of levels of aggressive coarsening 0
>   HYPRE BoomerAMG: Number of paths for aggressive coarsening 1
>
> However, when I add the BoomerAMG into my code, I got
>
> [3]PETSC ERROR:  
> ------------------------------------------------------------------------
> [3]PETSC ERROR: Caught signal number 11 SEGV: Segmentation  
> Violation, probably memory access out of range
> [3]PETSC ERROR: Try option -start_in_debugger or - 
> on_error_attach_debugger
> [3]PETSC ERROR: or see http://www.mcs.anl.gov/petsc/petsc-as/documentation/troubleshooting.html#Signal 
> [3]PETSC ERROR: or try http://valgrind.org on linux or man  
> libgmalloc on Apple to find memory corruption errors
> [3]PETSC ERROR: configure using --with-debugging=yes, recompile,  
> link, and run
> [3]PETSC ERROR: to get more information on the crash.
> [3]PETSC ERROR: --------------------- Error Message  
> ------------------------------------
> [3]PETSC ERROR: Signal received!
> [3]PETSC ERROR:  
> ------------------------------------------------------------------------
> [3]PETSC ERROR: Petsc Release Version 2.3.3, Patch 8, Fri Nov 16  
> 17:03:40 CST 2007 HG revision:  
> 414581156e67e55c761739b0deb119f7590d0f4b
> [3]PETSC ERROR: See docs/changes/index.html for recent updates.
> [3]PETSC ERROR: See docs/faq.html for hints about trouble shooting.
> [3]PETSC ERROR: See docs/index.html for manual pages.
> [3]PETSC ERROR:  
> ------------------------------------------------------------------------
> [3]PETSC ERROR: ./a.out on a atlas3-mp named atlas3-c36 by g0306332  
> Tue Jun 10 10:36:34 2008
> [3]PETSC ERROR: Libraries linked from /nfs/home/enduser/g0306332/ 
> petsc-2.3.3-p8/lib/atlas3-mpi
> [3]PETSC ERROR: Configure run at Tue Jan  8 22:22:08 2008
>
>
> Here's part of my code:
>
> call MatAssemblyBegin(A_mat_uv,MAT_FINAL_ASSEMBLY,ierr)
> call MatAssemblyEnd(A_mat_uv,MAT_FINAL_ASSEMBLY,ierr)
>
> call VecAssemblyBegin(b_rhs_uv,ierr)
> call VecAssemblyEnd(b_rhs_uv,ierr)
>
> call VecAssemblyBegin(xx_uv,ierr)
> call VecAssemblyEnd(xx_uv,ierr)
>
> call  
> KSPSetOperators(ksp_uv,A_mat_uv,A_mat_uv,SAME_NONZERO_PATTERN,ierr)
>
> call KSPGetPC(ksp_uv,pc_uv,ierr)
>
> ksptype=KSPRICHARDSON
>
> call KSPSetType(ksp_uv,ksptype,ierr)
>
> call PCSetType(pc,'hypre',ierr)
>
> call PCHYPRESetType(pc,'boomeramg',ierr)
>
> call KSPSetFromOptions(ksp_uv,ierr)
>
> tol=1.e-5
>
> call  
> KSPSetTolerances 
> (ksp_uv 
> ,tol 
> ,PETSC_DEFAULT_DOUBLE_PRECISION 
> ,PETSC_DEFAULT_DOUBLE_PRECISION,PETSC_DEFAULT_INTEGER,ierr)
>
> call KSPSolve(ksp_uv,b_rhs_uv,xx_uv,ierr)
>
> call KSPGetConvergedReason(ksp_uv,reason,ierr)
>
>
> The matrix changes every timestep so I have to call the  
> preconditioner every time. So what did I do wrong? Btw, the matrix  
> is A_mat_uv, RHS is b_rhs_uv and the answer is xx_uv.
>
> Thank you very much.
>
> Regards.
>
>