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Fixes from Pasqua

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Salvatore Filippone
2017-07-20 14:04:05 +01:00
parent eae18f1069
commit 7ec9000147
2 changed files with 13 additions and 13 deletions
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docs/src/gettingstarted.tex
+9 -9
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@@ -219,7 +219,7 @@ Furthermore, specifying block-Jacobi as coarsest-level
solver implies that the coarsest-level matrix is distributed
among the processes.
Figure~\ref{fig:ex3} shows how to set a W-cycle preconditioner which
applies no pre-smoother and 2 Gauss-Seidel sweeps as post-smoother,
applies 2 Gauss-Seidel sweeps as pre- and post-smoother,
and solves the coarsest-level system with the multifrontal LU factorization
implemented in MUMPS. It is specified that the coarsest-level
matrix is distributed, since MUMPS can be used on both
@@ -227,14 +227,14 @@ replicated and distributed matrices, and by default
it is used on replicated ones. Note the use of the parameter \verb|pos|
to specify a property only for the pre-smoother or the post-smoother
(see Section~\ref{sec:precset} for more details).
Note also that a Krylov method different from CG must be used to solve
the preconditioned system, since the preconditione in nonsymmetric.
The code fragments shown in Figures~\ref{fig:ex2} and \ref{fig:ex3} are
included in the example program file \verb|mld_dexample_ml.f90| too.
Finally, Figure~\ref{fig:ex4} shows the setup of a one-level
additive Schwarz preconditioner, i.e., RAS with overlap 2. The
corresponding example program is available in the file
additive Schwarz preconditioner, i.e., RAS with overlap 2.
Note also that a Krylov method different from CG must be used to solve
the preconditioned system, since the preconditione in nonsymmetric.
The corresponding example program is available in the file
\verb|mld_dexample_1lev.f90|.
For all the previous preconditioners, example programs where the sparse matrix and
@@ -282,20 +282,18 @@ boundary conditions are also available in the directory \verb|examples/pdegen|.
\begin{verbatim}
... ...
! build a W-cycle preconditioner with 2 Gauss-Seidel sweeps as
! post-smoother (and no pre-smoother), a distributed coarsest
! pre- and post-smoother, a distributed coarsest
! matrix, and MUMPS as coarsest-level solver
call P%init('ML',info)
call P%set('ML_TYPE','WCYCLE',info)
call P%set('SMOOTHER_TYPE','GS',info)
call P%set('SMOOTHER_SWEEPS',0,info,pos='PRE')
call P%set('SMOOTHER_SWEEPS',2,info,pos='PRE')
call P%set('SMOOTHER_SWEEPS',2,info,pos='POST')
call P%set('COARSE_SOLVE','MUMPS',info)
call P%set('COARSE_MAT','DIST',info)
call P%hierarchy_build(A,desc_A,info)
call P%smoothers_build(A,desc_A,info)
... ...
! solve Ax=b with preconditioned BiCGSTAB
call psb_krylov('BICGSTAB',A,P,b,x,tol,desc_A,info)
\end{verbatim}
}
\end{minipage}
@@ -314,6 +312,8 @@ boundary conditions are also available in the directory \verb|examples/pdegen|.
call P%set('SUB_OVR',2,info)
call P%bld(A,desc_A,info)
... ...
! solve Ax=b with preconditioned BiCGSTAB
call psb_krylov('BICGSTAB',A,P,b,x,tol,desc_A,info)
\end{verbatim}
}
\end{minipage}