update

[GMRES2stage.git] / paper.tex

diff --git a/paper.tex b/paper.tex
index e626ba05e614f730fb273627854e9d11c06ad6dc..dd80756de05bbab9ad5aad6523c520d9b459c3f3 100644 (file)
--- a/paper.tex
+++ b/paper.tex
@@ -615,7 +615,7 @@ points of our solver are given in Algorithm~\ref{algo:01}.
 
 In order to accelerate the convergence, the outer iteration periodically applies
 a least-square minimization  on the residuals computed by  the inner solver. The
 
 In order to accelerate the convergence, the outer iteration periodically applies
 a least-square minimization  on the residuals computed by  the inner solver. The

-inner solver is a Krylov based solver which does not required to be changed.
+inner solver is based on a Krylov method which does not require to be changed.

 
 At each outer iteration, the sparse linear system $Ax=b$ is solved, only for $m$
 iterations, using an iterative method restarting with the previous solution. For
 
 At each outer iteration, the sparse linear system $Ax=b$ is solved, only for $m$
 iterations, using an iterative method restarting with the previous solution. For


@@ -768,22 +768,20 @@ the restart  of GMRES is performed every  30 iterations, we have  chosen to stop
 the GMRES every 30 iterations, $max\_iter_{kryl}=30$).  $s$ is set to 8. CGLS is
 chosen  to minimize  the least-squares  problem with  the  following parameters:
 $\epsilon_{ls}=1e-40$ and $max\_iter_{ls}=20$.  The external precision is set to
 the GMRES every 30 iterations, $max\_iter_{kryl}=30$).  $s$ is set to 8. CGLS is
 chosen  to minimize  the least-squares  problem with  the  following parameters:
 $\epsilon_{ls}=1e-40$ and $max\_iter_{ls}=20$.  The external precision is set to

-$1e-10$  (i.e. ).   Those experiments
-have been  performed on  a Intel(R)  Core(TM) i7-3630QM CPU  @ 2.40GHz  with the
-version 3.5.1 of PETSc.
+$\epsilon_{tsarm}=1e-10$.  Those  experiments have been performed  on a Intel(R)
+Core(TM) i7-3630QM CPU @ 2.40GHz with the version 3.5.1 of PETSc.

 
 
 In  Table~\ref{tab:02}, some  experiments comparing  the solving  of  the linear
 systems obtained with the previous matrices  with a GMRES variant and with out 2
 stage algorithm are  given. In the second column, it can  be noticed that either
 gmres or fgmres is used to  solve the linear system.  According to the matrices,
 
 
 In  Table~\ref{tab:02}, some  experiments comparing  the solving  of  the linear
 systems obtained with the previous matrices  with a GMRES variant and with out 2
 stage algorithm are  given. In the second column, it can  be noticed that either
 gmres or fgmres is used to  solve the linear system.  According to the matrices,

-different preconditioner is  used.  With the 2 stage  algorithm, the same solver
-and  the same  preconditionner  is used.   This  Table shows  that  the 2  stage
-algorithm  can  drastically  reduce  the  number  of  iterations  to  reach  the
-convergence when the  number of iterations for the normal GMRES  is more or less
-greater than  500. In fact  this also depends  on tow parameters: the  number of
-iterations  to  stop  GMRES  and   the  number  of  iterations  to  perform  the
-minimization.
+different  preconditioner is used.   With TSARM,  the same  solver and  the same
+preconditionner is used.  This Table shows that TSARM can drastically reduce the
+number of iterations to reach the  convergence when the number of iterations for
+the normal GMRES is more or less  greater than 500. In fact this also depends on
+tow  parameters: the  number  of iterations  to  stop GMRES  and  the number  of
+iterations to perform the minimization.

 
 
 \begin{table}
 
 
 \begin{table}


@@ -813,14 +811,14 @@ torso3             & fgmres / sor  & 37.70 & 565 & 34.97 & 510 \\
 
 
 
 
 
 

-In   the   following  we   describe   the   applications   of  PETSc   we   have
-experimented. Those applications  are available in the ksp  part which is suited
-for scalable linear equations solvers:
+In order to perform larger  experiments, we have tested some example application
+of PETSc. Those  applications are available in the ksp part  which is suited for
+scalable linear equations solvers:

 \begin{itemize}
 \item ex15  is an example  which solves in  parallel an operator using  a finite
   difference  scheme.   The  diagonal  is  equals to  4  and  4  extra-diagonals
   representing the neighbors in each directions  is equal to -1. This example is
 \begin{itemize}
 \item ex15  is an example  which solves in  parallel an operator using  a finite
   difference  scheme.   The  diagonal  is  equals to  4  and  4  extra-diagonals
   representing the neighbors in each directions  is equal to -1. This example is

-  used  in many  physical phenomena  , for  exemple, heat  and fluid  flow, wave
+  used  in many  physical phenomena, for  example, heat  and fluid  flow, wave

   propagation...
 \item ex54 is another example based on 2D problem discretized with quadrilateral
   finite elements. For this example, the user can define the scaling of material
   propagation...
 \item ex54 is another example based on 2D problem discretized with quadrilateral
   finite elements. For this example, the user can define the scaling of material