From 0ee2d62e3d35e4ccd0a008a1b78fd5275926202e Mon Sep 17 00:00:00 2001 From: Timo Heister Date: Wed, 15 Nov 2017 09:59:58 -0500 Subject: [PATCH] update PETSc PreconditionLU documentation, take 2 --- include/deal.II/lac/petsc_precondition.h | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/include/deal.II/lac/petsc_precondition.h b/include/deal.II/lac/petsc_precondition.h index 092474c041..053c54ab75 100644 --- a/include/deal.II/lac/petsc_precondition.h +++ b/include/deal.II/lac/petsc_precondition.h @@ -562,11 +562,15 @@ namespace PETScWrappers /** - * A class that implements the interface to use the PETSc LU preconditioner (@p PCLU). + * A class that implements the interface to use the PETSc LU preconditioner + * (@p PCLU). Unlike classes like PreconditionILU, this class usually + * (depending on the settings) performs an exact factorization of the + * matrix, so it is not necessary to wrap it in an iterative solver. This + * class is typically used with SolverPreOnly to get a direct + * solver. Alternatively, you can use PreconditionerBase::vmult() directly. * * @note This is not a parallel preconditioner so it only works in serial - * with a single processor and only when using a - * PETScWrappers::SparseMatrix. + * computations with a single processor. * * @ingroup PETScWrappers * @author Oliver Kayser-Herold, 2004 -- 2.39.5