From: lilia Date: Mon, 18 Aug 2014 15:08:09 +0000 (+0200) Subject: v2 X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/GMRES2stage.git/commitdiff_plain/1082caa290770800e8a7f6815ed153931cd93460?ds=sidebyside v2 --- diff --git a/paper.tex b/paper.tex index 381954b..185bbf3 100644 --- a/paper.tex +++ b/paper.tex @@ -553,24 +553,25 @@ Iterative Krylov methods; sparse linear systems; error minimization; PETSC; %à %%%********************************************************* %%%********************************************************* \section{A Krylov two-stage algorithm} +We propose a two-stage algorithm to solve large sparse linear systems of the form $Ax=b$ based on iterative Krylov sub-space methods. \begin{algorithm}[!h] \caption{A Krylov two-stage algorithm} \begin{algorithmic}[1] -\Input $A$ (sparse matrix), $b$ (right-hand side) -\Output $x$ (solution vector)\vspace{0.2cm} -\State Set the initial guess $x^0$ -\For {$k=1,2,3,\ldots$ until convergence} -\State Solve iteratively $Ax^k=b$ -\State Add vector $x^k$ to Krylov basis $S$ -\If {$k$ mod $s=0$ {\bf and} not convergence} -\State Compute dense matrix $R=AS$ -\State Solve least-squares problem $\|b-R\alpha\|_2$ -\State Compute minimizer $x^k=S\alpha$ -\State Reinitialize Krylov basis $S$ -\EndIf -\EndFor + \Input $A$ (sparse matrix), $b$ (right-hand side) + \Output $x$ (solution vector)\vspace{0.2cm} + \State Set the initial guess $x^0$ + \For {$k=1,2,3,\ldots$ until convergence} + \State Solve iteratively $Ax^k=b$ + \State Add vector $x^k$ to Krylov basis $S$ + \If {$k$ mod $s=0$ {\bf and} not convergence} + \State Compute dense matrix $R=AS$ + \State Solve least-squares problem $\|b-R\alpha\|_2$ + \State Compute minimizer $x^k=S\alpha$ + \State Reinitialize Krylov basis $S$ + \EndIf + \EndFor \end{algorithmic} \label{algo:01} \end{algorithm}